156 yrd distance, 160 yrd club used ,hit at 95% with a -2 lower hole than ball and the shot come ups 20 yrds short?
Your backswing % is not proportional to the distance of the club. 95% of 160 with straight math would be 152. But, since the numbers aren't proportional, I could see where that shot came up 20 yds short, especially if you didn't ding it and wind was involved.
Something else that changes when you move up is the part of the game that needs to see what you do as a TM. It's like starting over where that part of the game is concerned and you need to establish your new tier profile.
That's also why your average will be all over the place until you get enough rounds in to saturate it--the game is checking you out as a TM and making your game miserable (for now.) Stick with it, it'll get better.
And when that's over you get to go through it all again as a Legend. :-)