Spigner had an article in Bowler's digest, the article had pictures of three balls rolled by the same bowler, the tracks were marked. Each ball had a different track. High rev players will get flare in the air with today's weight blocks. If it's flaring the PAP is migrating I believe.
"Great minds discuss ideas; Average minds discuss events; Small minds discuss people."
Be well, John K. in Glendale Az.