Programming

Input speed is not "just" input speed.

Note: I'm not about to argue for or against modal editors, I just want to answer: why is input speed really really really important, when (we agree) its not a big percent of total time.

5min at 80mph over a bumpy dirt path is very very different than 5min of flat smooth straight driving. And not just because of effort.

A senior and junior dev could spend the same amount of time to rename a var across 15 files, move a function to a new file, comment out two blocks, comment one back in, etc. But. When I try to have a conversation while they do that, or when I change my mind and tell the junior to undo all that, its a massive emotional drain on the junior.

But effort isn't the whole picture either: speed is a big deal because pausing a conversation/mental thought for 5 seconds while you wait to finish some typing, is incredibly disruptive/jarring to the thought-process itself. That's how edge cases get forgotten, and business logic gets missed.

Slower input is not merely input time loss, it also creates time loss in the debugging/conceptualizing stages, and increases overall energy consumption.

If the input is already fast enough that there's no "pauses in the conversation" then I'd agree, there's not much benefit in increasing input speed further. BUT there's almost always some task, like converting all local vars (but not imported methods) in a project to camel case, that are big enough to choke the conversation, even for a senior dev. So there's not necessarily a "good enough" point because it's more like decreasing how often the conversation gets interrupted.