I'd suspect that was because of the amount and length of oil on the lanes.
Realize that the Red/Purple has a different coverstock and a different surface preparation (2000 grit Abralon + Polish) that allows it to be used on light to medium-light oil, while the Blue/Silver's Coverstock is slightly earlier reacting with an earlier surface preparation (4000 grit Abralon matte/dull), which allows it to handle medium-light to medium oil.
In the BTM review of these balls, the Red/Purple got a length of 17 in stock form, while the Blue/Silver got a length rating of 14 in stock form. That's a fairly large difference. There's be less difference if they had the same surface but they'd still be different.
"None are so blind as those who will not see." "Some bowlers are crazy as pickled cats."
Edited by charlest on 2/1/2011 at 8:34 AM