Seriously, this is the heart of it. The one thing about Emacs that I just can't forgive is its insistence over the decades on mixing tabs and spaces in its auto

Seriously, this is the heart of it. The one thing about Emacs that I just can't forgive is its insistence over the decades on mixing tabs and spaces in its auto-indentation. Ultimately, the spaces vs. tabs debate really comes down to which policy is less likely to result in mixed tabs/spaces. If people use tabs, it seems inevitable that some spaces will sneak in there as well. If people use spaces, tabs are unlikely to sneak in. Obviously that's a combination of common default editor configs and human behavior, but that's just how it works out in practice.