Howdy neighbor :)

100 wpm in 6-12 months is a tough goal coming from 75-80 wpm. I don't mean to discourage you at all, but I was at 72 wpm before the switch and after 6 months after I'm at 56 wpm (in the test I use as reference). That's close to 80% from where I started at, and certainly acceptable (in fact I found anything above 40 wpm to be acceptable, which took about 3 weeks to reach). But I found it was hard to "unlearn" my ~15 years of Qwerty/Qwertz experience, or rather to get new experience with Colemak. I figure I'll be faster than I was maybe in another six months.
Of course there are those who got quicker much faster, and maybe others who take longer. Either way I figure it's well worth it in the long run, but in the beginning one needs lots of discipline. ;)

Anyway, good luck!

It may be unrealistic to expect that Colemak will let you type significantly faster than you already could with QWERTY.   Peak typing speed is bounded more by innate athletic ability than it is due to any hobbling effect of QWERTY,  so it's unlikely you will gain more than a thimbleful of wpm over your QWERTY best, even after much practice. 

However, Colemak is more comfortable and lets you type longer with less fatigue.  That, rather than speed, may be more crucial for someone trying to get out that thesis or dissertation.  It's not the speed with which the words tumble out, it's the stamina to keep at it.

But rest assured you will not pay a speed penalty by switching to Colemak.   As the many progress reports here show, typists invariably regain their original speed after only a few weeks.