i would definately talk to whoever is drilling your balls about your predicament. have him watch you for a few games, and see what he thinks of what your saying. i would definately be worried about overlap between the g3 and the blue sparkle. i dont think you'll have any problems with the burgundy or the blue slate, but if you do, sanding or polishing should correct these problems.
i wouldn't just look at drill patterns, but also pin length, top weight, weight holes, and side weight. all these play a factor in how the ball is going to react on the conditions you are looking at. Hopefully your driller is knowledgeable enough to help you out some here, and doesn't just give you label drillings on everything.
do not be so worried about having every condition covered. since your high series is a 6 somethin, im guessing that you probably average in the 170 range. at this point, i dont think having every condition covered will help as much as some good old practice. 3 balls at your level plus a spare ball would pretty much be all you would need. Having anymore balls then that will just make you not use some/switch too much between balls when it might just be inconsistency that is causing the problem.
I see so many bowlers with 5 million balls that just get confused when they have too many balls, or after shooting an amazing game, switch balls because the lanes are drying out only to shoot a bad game after. For the league bowler who is looking to excel on a THS, sticking with one ball through a 3 game set and just moving feet and target accordingly is usually the best bet to winning pot games. Once you start wanting to have a chance in tourneys, thats when buying a new ball and trying a new drill might pay off. That ball might just be matched up to what you a looking for and be the perfect ball for the condition. You win the tourney and the ball pays for itself and much more.
Work out a good relationship with some of the old pros at wherever you bowl and the owner. This will help with practice costs, practive efficiency, etc. you know, if you go 9/ every frame, you'll shoot 190. Now granted, with THS, you are bound to get at least a few lucky breaks every game.
So work on your spare game. Keep track of how many misses you have each game (A miss is considered missing any spare not a split, washouts and baby splits count as misses). once you get down to the level of under averaging under 1 for a 3 game set, you'll be amazed at how much your game has improved. it not only improves your accuracy on spares, but also on strikes. What i would suggest for spares first is screw the urethane, its too strong, and get a plastic ball. If you have to get it from another company, you're only out prolly 75 bux.
In practice, figure out where to stand and what target to throw at on each and every spare you can think of. Straighter is greater, the possibilities of chops is deterred. Just keep working on your spares with whatever practice routine you like, there are many out there. Some like throwing first ball at 7 or 10 or whatever, second strike ball. Some ppl like low balling, shooting for a low score with gutters being strikes/spares. Some like shooting at baby splits, some like shadow bowling, etc. etc. Theres a ton of different ways to practice spares, and its one of the most overlooked aspects of the game by beginning bowlers.
Take advice from guys you know are good bowlers. hang around them and become good friends. It will pay off as you will find great pointers on hand position, finger position, axis rotation, ball selection, ways to move, proper form, etc. etc. Hope you take my advice because it will really pay off in the future!
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stanski