I remapped K to :grep for the word under the cursor instead. The way I did it, though, is such that if I give it the numeric prefix, it will do the man lookup in that section.

  :nmap K "_y:execute count ? ( ":!man " . count . " " . expand("<cword>") ) : ( ":grep \\<" . expand("<cword>") . "\\>")<CR>

I have it mapped to do :grep in visual mode also, without the fallback on man.

  :vmap K "zy:execute ":grep " . getreg("z")<CR>

Maybe newer Vim has a solution for "grep word under cursor"; it's such an obvious use case. I'm trained on K though.

> I'm trained on K though

I hear you, have an hard to overcome ctrl-d muscle memory from back in my sublime-text days. Which unfortunately conflicts a little with vim's default ctrl-d in some modes.

But for the most part I was surprised how much muscle memory I could re-wire when I forced myself. I think so long as you pick one at a time, and are using it for a solid chunk of time, i.e while you are working, then it doesn't take long, ~1 week maybe until it's 90% instinct.

I think I probably need to finally shake ctrl-d, maybe today is the day.

In Vim, I use Ctrl-T to indent, and Ctrl-D to deindent (in cases where automation doesn't handle it). Ctrl-T works with the correct indentation amount which is defined by the value of "shiftwidth"; whereas the Tab key inserts a tab, or spaces to get to the next tabstop if "expandtab" is in effect.

I trained myself on Ctrl-T more than 20 years ago; some people remap the Tab key to indent.