Thought I would chime in and agree with Kat here - a calculator is an aid, and for those who use them, I have no issue at all with that. It is no different than using putter/shot pal with a calculator sitting next to your laptop/pc.
Back when I used to be reasonably good at golf, I would have course notes, especially from my clubs course and could tell you every nook and cranny, distances to the front, middle and back of the green from virtually everywhere.
When I played in a tournament anywhere, I would make a point of playing the course several times if possible, write notes and get yardage charts if possible.
Now in this game I play by feel. and perhaps I really should use an aid like Kat's, because some days I play like a hack. In this game I have always been too lazy to write notes, or even calculate shots, because it is only a game and I play for fun.
The more rounds I play, the better I have become.......well some days - I still have brain farts, finger farts etc, On approach shots I do vary in my guestimates and an aid would no doubt give me consistency, but most of my good rounds are for one reason - I read the line of the putts better. An aid like Kats will not do this for me.