I recently bowled on the USBC Masters pattern in my PBA Experience league.  Before I say anything more, I want to state that I do not know a lot about pattern graphs and whatnot.  However, that shot is supposedly incredibly flat.  To me, that would mean that if for example one is playing directly up the boards (pick one, it doesn't matter) that the ball should start hooking at a set distance off the end of the pattern.  For example (I'm just making these numbers up) if you played right up the 5 board, your ball would make it's move at say 43'.  If you played up 20, your ball would make it's move at that same 43'.  I realize lane topography, humidity, etc. all play a role in ball reaction.  But on a "flat" pattern, how can outside of 8 be unplayable but inside of 11 the ball takes off?  If anything, wouldn't the outside line see a ball starting up sooner?  I didn't perform too terribly on the shot, but I'm trying to understand why a shot up 5 would take out the 3-pin but a shot up 12 would take out the 4-pin.  

Don
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"On-base percentage is great if you can score runs and do something with that on-base percentage.  Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool

Well, while there are always exceptions to the rule, flat conditions are often played as if they were a reverse block, showing exactly the ball reaction that you saw. Many (but, not all) flat conditions are oiled to 40 feet to 50 feet; such longer oil patterns should, IN GENERAL (that means not every time, but most times), be played from deep to deeper inside angles. Shorter oil patterns are played further and further outside. The shorter they are the further outside you should play them.

Of course the trasition will play differently and often with much difficulty, depending on the breakdown caused by the type of oil, the type of lane surface, the type of bowler who bowled on them, and what balls they used and what lines they played.
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