There now are 15 approved 900 series by 14 different bowlers, with two bowled in the past month now approved by the United States Bowling Congress. Unfortunately, the most legitimate 900 ever rolled -- the first in July 1982 by Hall of Famer Glenn Allison with a plastic Columbia Yellow Dot on a lane condition that didn't pass muster under the rules back then but which would be a standard condition today -- remains unrecognized by USBC....