>Since most my time is spent concentrating on understanding code, the last thing I want is an editor that forces me to consciously think about text operations. "d[downkey]4" might be theoretically more efficient, but I spend way less cognitive energy holding down the shift key and pressing the down arrow 4 times.
The point is well taken, but don't forget that for most people that downside of increased cognitive pressure goes away after a few days or weeks of regular vim usage. I've been using it for about a year and all the combos I normally use are second nature to me (and have been for months). Don't underestimate the human brain's ability to grow and adapt and for incredibly complicated things to quickly turn into routine.
For the record, I almost never use vim's much touted hit a number key then an action to do it n times feature. I have modified it so j and k do the normal down/up one line and J K go down/up seven lines or so for scrolling. [1] If I'm doing something like deleting a line and have to delete a bunch (common case), then I'll "dd" to delete line and then hit "." (which repeats the last action) three or four times until satisfied. Way easier than counting the number of lines to delete then typing "4dd" imo.
[1] Note for anyone who wants to duplicate this: it was still unbearably slow to just hold down J or K to scroll because the default delay between depressing a key and when OSX decides you are actually holding it down and not just pressing it once is too long. Decrease it in the native settings of your OS for a smoother experience.