skccvb: if you don't factor in 'spin'- both clubs and balls- you are only getting a 'helpful' approximation- not exactness
Spin, Distance, Precision ... that's the "feel" part of the game ... some are better than others. The calculator currently gives you an estimated distance and deviation. You have to know what your clubs do with the ball you're using to get your shot to said distance. Also, some holes play longer/shorter than what the distance shows. You need to know that as well ... also a part of "feel"
skccvb: however putting calculations are quite easy to do 'on the fly' - and you need to know thru experience that some putts play 'slow' and some 'fast'.
Once again "feel". The calculators won't play the game for you ... they will merely give you, as you say, an extremely good approximation to "what's needed" to get you close or sink the putt.
Programs are similar to people ... they need to learn to crawl before they can learn to walk. This calculator will continue to evolve because I'm writing it for me. Right now, it's learning to crawl.
My next major release will include "wind and club mapping", followed by "course and hole" mapping, which will take into account many of these "feel" factors. The calculator's basics are there, and, in time, will learn how "you" play and adjust it's variables to fit your game (so you don't have to think about it).
Many appreciate not having to calculate "on the fly" ... some like it. I fall under the "minimum effort, maximum benefit" category. I personally enjoy the AS and MP games over the RG's and single-play tourneys. Having the calculator gives me more time to socialize and less time dealing with "on the fly" calculations.