Agreed - I don't think the speed-limiting factor when reading code is how fast it transfers from screen to brain. That's totally different with prose, where you often skip over almost 90% of the characters because the choice of words that fit the context comes naturally - not quite the same for function call arguments...<p>A possible benefit of fixed-width: say you take a for-loop (which you can probably recognise even skipping over 95% of the characters) - now your brain wants to extract the indices at which it starts and ends: it seems to me a fixed-width font makes it easier to predict where you'll find the indices in the given line. (Not sure if that's how my eye-coordination really works, but it feels like it does...)