Never said it was. I spend a lot of time reading code. I read other peoples code every day. To a very large extent, that code is going to use various layout tr

Never said it was. I spend a lot of time reading code. I read other peoples code every day. To a very large extent, that code is going to use various layout tricks that are based on a monospaced font. Someone might line comments up like this: // 1. Blah blah, blah // blah and more blah. // 2. Second piece of blah. Arguments to a function might be lined up: void func(int arg1, int arg2... Someone might describe some detail of a network protocol with a diagram (as often seen in RFCs). A large comment block might be adjusted to fill out to a certain column width. I'm probably forgetting a ton of other layout tricks that people use. Almost all of them rely on a monospace font. Looking at code that wasn't specifically written for proportional fonts is death by a thousand cuts. The readability suffers greatly.