Like Chubbs said, some of the
AMF's are known for high friction, which means a strong backend reaction. Sometimes this leads to higher scores by allowing that extreme entry angle, even with a longer or heavier pattern. This can also make for harder scoring as a ball that jumps too much becomes hard to control. I just stopped bowling in an
AMF house that was high friction and often had a short light oil pattern. This wasn't the reason I stopped bowling there. It was challenging and I like a challenge. I know I could score on it, I did last season, but my swing was so out of whack that I couldn't move inside and consistently throw it correctly, same thing for playing outside with a very weak ball.
That's one of the great things about this game, there are so many variables, and in order to be a great bowler you have to have some knowledge involving most of them. It makes the game more of a thinking game, of course sometimes people will over think.