One of my co-workers said he could type over 140wpm using Colemak; I was skeptical stating that wpm is subjective and its results depend on the tools used. After he had fired up the typeracer website and posted 143 wpm on first try, he wasn't kidding. Using qwerty I'm only able to set 90 wpm on that website. He watched me type a few times and noted that one of my technique was wrong. He said I wasn't alternating my thumbs accordingly when spacing. After watching him a second time, I'm perplexed at how he was achieving this. I tried doing so but failed miserably. He described to me that using the thumb opposite to the last character typed will net me a faster typing speed. Does anyone else alternate their thumbs when typing? Therefore have I've been typing incorrectly this whole time by using only my right thumb to space each word? I'm thinking of learning Colemak using this technique to see if it helps.