Yeah, the Blurple might have too strong a cover for a really short oil pattern. Actually, though, a Green/Blue Centaur with some polish might be great -- smooth, not jumpy, a solid that really gets down the lane...could be good.
I would go:
No Mercy - You already have it, for heavier, longer stuff
Pumpkin - Maybe a little polish, maybe a surface change for fresh mediums.
Blurple - really nice, get this ball NOW, strong roll with good length for when the lanes start to break down a little, or when the Pumpkin doesn't quite turn the corner. Go with maybe a 4.5-5 pin-PAP distance. THIS BALL IS SO MONEY!!!!!!!!!!!!!! (I swear, I'm not excited about the Blurple)
Blue-Green - ultra low differential solid for short patterns, add polish, with maybe a high pin placement, not leverage, something like 4-5 from your PAP and over the fingers.
Spare Ball
I have never heard of "too much" oil at Gold...only people complaining about not enough. So I don't think you could go wrong with having a few weaker balls...remember, they might let you play straighter, which could always give you an edge over the field.
There is a gap between the Blurple and the Blue-Green, but I have a feeling that you could either move in with the Blurple, if you have enough hand (and by reading your profile, you do), or move right, with the Blue-Green, and still be fine.
Good luck!
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I am the University of Virginia's Bowling Team. After all, one All-American is all you need.
Edited on 5/10/2007 3:17 PM