I had exactly the same issues with the shift keys when I first started out with 'proper' touch typing.  It really put a dampner on doing the tutorials - as it would really upset my flow.  I did however force myself to use opposite hands when shifting, but occasionally I'll use the same hand if it feels better.

For longer words that are all caps - how about just getting into the habit of using the caps-lock - that's what it is there for.  And it's easier.  With caps and double quotes (which requires cat like prowess,) you might want to look at sticky keys.

I think the simultaneous key presses are a hangover from the manual typewriter days.  I used to think that chords would be the answer to all my prayers but doubt that now.

Text input aids such as auto-caps and correct spacing after a full stop - would surely help this.

Possibly change your practice prose when starting out, some texts are dialogue heavy - and are a real pain.  I took the top 200 most common words, and placed them in a text file and practiced them, knowing that the majority of the language would be catered for that way.

ISO Dvorak places the double quote nearer the home row (in Qwerty's Q position) - some forward thinking there.

If you just keep at it, you'll overcome the initial hurdle though.

Thanks for the tips.

It has now been 23 days since I started learning Colemak. Results so far:

Day:    Avg.    High    Low    Median
Day 2    17,66    24    11    18
Day 3    23,98    29    18    24
Day 4    26,74    34    19    26,5
Day 5    29,62    38    21    29,5
Day 6    30,87    41    25    30
Day 7    33,82    40    27    34
Day 8    37,60    44    29    39
Day 9    41,42    51    34    42
Day 10    43,80    54    34    44
Day 11    46,17    56    37    46
Day 12    48,53    60    40    48
Day 13    49,72    58    41    50
Day 14    50    59    41    50
Day 15    50,68    61    42    51
Day 16    52    65    45    53
Day 17    54,50    66    48    55,5
Day 18    61,35    73    50    61,5
Day 19    60,15    72    55    60
Day 20    61,19    73    49    62
Day 21    61    73    50    61
Day 22    64,13    77    54    63,5
Day 23    65,51    75    54    67

My best results:
Hi-games.net: 77 wpm
Typeracer: 77 wpm
Amphetype: 77.6  wpm
10 fast fingers: 84 wpm

I lately started using Amphetype, and I have discovered there's a huge difference in my typing speed for different keys. My fastest are (counting only letters): h(???) (105.1 wpm), b (101.9 wpm), a (97.1 wpm), t (95.3 wpm) and w (92.1 wpm). At the lower end of the spectrum: j (22.2(!) wpm), z (49.4 wpm), x (52.2 wpm), k (52.2 wpm), p (60.3 wpm), g (62.7 wpm).

I guess it should come as no surprise that my fastest keys are those that are the same as in QWERTY, but I for sure wouldn't have expected the "H"-key to be on top.

I have to say that Amphetype is really useful for identifying one's weaknesses.

By the way, according to Amphetype my most damaging key is "space", which is also my fastest. Anyone knows based on what this is calculated? I don't understand how it could possibly be the most damaging key if it's also the fastest.

Ahhh... Literally, physically "damaging". :D I don't know why that didn't even occur to me. I assumed it was something about breaking the flow of typing or something. Thanks.

So the time has come to sum up the first month of my Colemak experience (results below from Hi-games 1 minute tests):

Day    Aver.    High    Low    Median
-------------------------------------------
Day 2    17,66    24    11    18
Day 3    23,98    29    18    24
Day 4    26,74    34    19    26,5
Day 5    29,62    38    21    29,5
Day 6    30,87    41    25    30
Day 7    33,82    40    27    34
Day 8    37,60    44    29    39
Day 9    41,42    51    34    42
Day 10    43,80    54    34    44
Day 11    46,17    56    37    46
Day 12    48,53    60    40    48
Day 13    49,72    58    41    50
Day 14    50    59    41    50
Day 15    50,68    61    42    51
Day 16    52    65    45    53
Day 17    54,50    66    48    55,5
Day 18    61,35    73    50    61,5
Day 19    60,15    72    55    60
Day 20    61,19    73    49    62
Day 21    61    73    50    61
Day 22    64,13    77    54    63,5
Day 23    65,51    75    54    67
Day 24    67,26    75    61    66
Day 25    67    77    60    66,5
Day 26    66,92    77    60    67
Day 27    68,07    82    60    67
Day 28    68,62    80    60    69
Day 29    73,21    80    64    73
Day 30    72,98    87    63    72
-------------------------------------------

Personal bests:       
-------------------------------------------
10 fast fingers:    106    2012-09-30
Hi-games (1m):    87    2012-09-30
Amphetype:    96,2    2012-09-30
Typeracer:    98    2012-09-30
-------------------------------------------

That my result is better in 10 fast fingers is of course because it doesn't have any punctiation or other "weird" special characters, and that it has a limited set of very common words. Earlier today I scored 100 wpm with 15 misspelled words, so there's definitely much room for improvement. In Typeracer I have seen my speed being above 110 wpm for more than 10 seconds a couple of times.

My analysis:
Before starting with Colemak I assumed that starting with a new keyboard layout would be synonymous with going back to square one, but this was not at all the case (at least not with Colemak). It's more like going back to square three (out of ten let's say), but this time run through the track you already know and easily dodging the obstacles that caused so much problems the first time.

So far I don't actually use Colemak in practice (neither at work, nor at home), though (just for practising at Hi-games, Typeracer etc) as I find it quite annoying to "get started" typing each time after using the mouse (I still have to search a bit for the homerow default finger position). This post is written entirely in Qwerty. ;)

I still feel there's a lot of room for improvement, so I guess I will continue practising for as long as I continue to make decent progress (and have time). I still don't really know if I will make the full switch to Colemak, though. It's still, of course, a lot more convenient for me to use my old method of typing (even if I have to move my fingers a lot more) since I don't really have to think or focus when using it. I tend to make a lot of errors with Colemak when I don't focus carefully.

Overall my learning Colemak hasn't had much influence on my old typing method, but I have noticed that on days when I have practised much Colemak and type something slowly with my old method, I tend to start thinking and using more fingers than I "should" and mixing up keys a bit, but it hasn't really been a big problem.

It has now been 1.5 months since I started practising Colemak.  Here is my latest progress report:

Personal bests (WPM):       
10 f. fingers:    106    2012-09-30
High-games:    92    2012-10-10
Amphetype:    101,8    2012-10-14
Typeracer:    99    2012-10-10 (Average of last 10 races: 84)

Average WPM on day 45 at hi-games.net over twenty 1-minute attempts: 79,4 (max: 88, min: 72, Median: 80,5)

Progress has, as could be predicted, slowed down a lot. No big improvements of personal bests, but at least the minimum speeds seem to be on the rise. My typing seems to be fluctuating a lot with bursts of speed over 120 WPM with occasional mistakes breaking the rhythm and ruining the speed and experience a lot. Probably I should try to focus on hard to type words/finger sequences.

After two months of Colemak:

Personal bests:       
10 fast fingers:    113    2012-10-29
High-games:    94    2012-10-20
Amphetype:    112.9    2012-10-30
Typeracer:    102    2012-10-27

My average WPM is around 82 on 1-minute attempts at hi-games.net, so during the second month I have improved around 9 WPM (average speed). I have a feeling that I'm really typing a lot faster now than I did at the end of the first month, but I also have the feeling that the faster I type, the longer it takes for me to recover from my errors, which also ruins the rhythm, so the average speed hasn't improved all that much.

Three months have now passed since I started learning Colemark.

Personal bests:       
10 fast fingers:        129    2012-11-17
High-games (1 min)    105    2012-11-29
Amphetype:        128    2012-11-24
Typeracer:        116    2012-11-30

Average WPM on day 92 at hi-games.net over twenty 1-minute attempts: 91.75 (max: 104, min: 82, Median: 94) which means my average speed has improved almost 10 WPM since last month which is better than last month's progress.

Monthly averages/bests at Typeracer:

Month            Average    Best
------------------------------------
November 2012    92.97    115.54
October 2012    78.94    102.49
September 2012    66.76    98.20

Still making steady progress, now with short bursts of speeds over 140 WPM.

It more and more seems to me that the eventual limit of speed for touch typing and Colemak is not really about finger movement itself (as was the case with my previous method), but rather about finger "twisting" which is very noticeable when doing the 10 fast fingers test.

I guess what I really mean is that instead of actually moving the whole hand as with my old method of typing I have to bend my fingers and stretch them in weird ways a lot, which feels a bit awkward when typing certain combinations of letters. But I guess the only way to solve that problem would be to learn to use different fingers for the same keys depending on the sequences.

After four months:

Personal bests:       
10 fast fingers:        132    2012-12-17
High-games (1min):    110    2012-12-17
Amphetype:        128    2012-11-24
Typeracer:        123    2012-12-29

Hi-games.net bests:

Game        Score        Rank       
Typing Test: 5 Minutes
        99 wpm        #127
Typing Test: 30 Seconds
        122 wpm    #180
Typing Test: 1 Minute
        110 wpm    #204
Typing Test: 2 Minutes
        104 wpm    #218

Typeracer:

Month    Average    Best    Races    Wins    Win %
December 2012    102.88    122.80    125    67    53.60
November 2012    92.97    115.54    410    184    44.88
October 2012    78.94    102.49    515    163    31.65
September 2012    66.76    98.20    267    80    29.96

Average WPM on day 123 at hi-games.net over twenty 1-minute attempts: 96.24 (max: 108, min: 82, Median: 88).

Wow. Another success story.

Half a year has now passed since I started using Colemak.

Personal bests:

10 fast fingers:        140    2013-02-26
High-games (1min):    123    2013-02-10
Amphetype:        137,3    2013-01-19
Typeracer:        126    2013-02-05

Hi-games.net:

Game        Score        Rank       
Typing Test: 5 Minutes
        104 wpm        #103
Typing Test: 1 Minute
        123 wpm        #108
Typing Test: 30 Seconds
        131 wpm        #133
Typing Test: 2 Minutes
        108 wpm        #177

Typeracer averages by month:

Month    Average    Best    Races    Wins    Win %
February 2013    111.22    126.17    69    43    62.32
January 2013    107.51    122.45    105    55    52.38
December 2012    102.88    122.80    125    67    53.60
November 2012    92.97    115.54    410    184    44.88
October 2012    78.94    102.49    515    163    31.65
September 2012    66.76    98.20    267    80    29.96

Average WPM on day 183 at hi.games.net over twenty 1-minute attempts: 101.80 (max: 109, min: 90, Median: 102.5).

I also attempted a 50-minute test at hi-games.net and reached 95 WPM without any discomfort or fatigue whatsoever to the hands or fingers (just my eyes were a bit tired). I would never have been able to accomplish that with my old method of typing for sure.

Nice! Congratulations on your efforts and their fruits.