I learned programming with Eclipse default settings and Java, on a PC with a classic AZERTY straight keyboard with 105 keys layed out in the classic way. At some point there's not debate, yeah Java is crap, yeah Eclipse is laggy, etc, but my hands, brain and code work completely in concert when all those are united and there's no question that I can get anything done much, much faster with these. I actually gave up on using a macbook after a year and a half of constant practice because it still felt far too tiring to build my android apps compared to the PC, even though it was still Java and Eclipse.

It would be the equivalent of speaking your mother language (or native tongue or first language, whatever you english-speaking people call it :P) vs speaking a language with which you're "only" fluent when you just have to express a point very fast.

I'm not saying Notch is in the same situation (or anyone else actually), just that there are reasons, beyond being able to get things done using just the available tools, to use a setup that is often seen as suboptimal.