There are two levels of slowness being talked about here, both valid. One is that 16ms vs. 60ms response to typing and touch. The other is yours, and I think yours is the more problematic one. Not only do those multi-second waits accumulate through the workday to be a significant fraction of the day, but each one presents an opportunity for the user's mind to wander, or other parallel tasks to be switched to, with a high cost of returning to the current state.