Can't access the article due to database error, but since we're discussing keyboard layout effectiveness for developers:

If we were indeed limited by input, why wouldn't this come up in discussions about languages like CoffeeScript (or even Python/APL) that save keystrokes to begin with? In the case of Coffee and Python, the keys saved are actually the hard-to-press symbols as well. And yet I've never heard the point come up.

Perhaps this is more about our need to feel superior by adopting a routine of cargo-cult efficiency than anything else. In the broader view of productivity, optimising keyboard layouts is more like optimising memcpy() in C. While it may bear some results, it's rarely the actual bottleneck.