...Except Zed's whole point with this is that you don't have to use the fancy Cygwin/POSIXy stuff or a Linux Live CD or whatever to do programming and the command line. POSIX environments are better for programming, but you don't need them, and a lot of the people who would benefit most from learning programming don't have Linux experience and wouldn't do it if they had to do something fancy to get a UNIX-y environment.

For me it's more a matter of cognitive simplicity.

I can use a POSIX environment anywhere. It's one less hurdle if that's the tool I'm using.

I've learned (and forgotten) numerous proprietary system languages. I prefer sticking with stuff that will be around. POSIX/Unix/Linux have demonstrated staying power.