When talking about carry down for the most part, it's looked at as just oil being pushed down from the heads to the backend. Now in the Oct.08 BTM they had article saying it's oil depletion because of oil absorption by the ball coverstocks rather than carrydown.
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I think it's a combination of both depletion and carrydown. But it's where it's being carried too that's the thing. The graph in the article show's lot's of oil depleted from the first part of the heads and they found little being transfered to the backend.
But if you look toward the mid-lane area the oil is not being depleted there like it is in the heads. I think that's because the head oil is being pushed into that area, with very little making it to the backend. Because by the time the ball make's it there the coverstock has absorbed most of it.
So now you have a dryer heads, a mid-lane that still has oil and backend still relatively dry. So if you keep playing the same basic line, Your high friction aggressive ball will start losing power in the heads.Then hit the mid-lane oil skid and go a little longer and be doa down through the backends.
Now your low friction hard surface ball (which you'll likely be putting more speed on)will get through the heads, but then when hitting that mid-lane oil it will go long and over shoot the break point, Looking like it's carrydown not letting it come up.
Which is why it looks like neither ball is working.
Now this wouldn't be true all the time, it would depend a lot on who else is bowling on your pair of lanes and the balls and lines they used. Say a lot of plastic balls are used, they would tend to push more oil, rather than absorb it. Thus you'd have more true carrydown.
As for what to do, that would depend on the style of bowler. I find I can stay with my ball by moving right and changing my release some. Or sometimes I'll move right and change to my particle pearl.
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