No argument on the inflated averages, but its not inflated for everyone. The average average for males in sanctioned competition is somewhere in the low, maybe mid 170s. I think females its in the mid 140s maybe low 150s. My whole career in bowling has been in the current resin era, actually this current decade, so its all I've ever known. If and when I get my mechanics fixed I believe I can score well with a plastic on most typical house shots, maybe not carry as many shots but still put it in the pocket and get at least 9 just about every strike shot. As long as my game is in order I have no problems bowling harder conditions. If my game wasn't such a mess I would be bowling at least one PBA league this summer. My winter leagues I try to bowl at a different house and hope they don't play the same so that I have to learn to be versatile.

Well, the hardness durometer reading of 72 became a requirement in 1976, after the introduction of polyester balls. That's about 10 years later. This had no impact on the rubber balls of the 60's and early 70's.

What about acetone?

It doesn't mean you can't bowl on those conditions, it just means you can't get the ideal 6-degree entry angle. Because there's no possibility of opening your target, it puts a premium on accuracy over shotmaking, I suppose...

I guarantee you can get a 6 degree entry angle on 24 feet of oil. Which is why I thought the formula was so amusing to begin with.

Really? What do you do?

(I bowled on a lane with really short oil once. After enough gutter balls, I decided to switch over to a straight ball.)

Acetone being banned is tied directly with the hardness rule. It was used to soften up the polyester balls for better grip and thats when both the ban on using acetone on balls and the hardness Durometer were enacted.

Bleeder in a tub of Acetone and bam 64-65 on the durometer and hook the whole lane with it.

Just found something that was interest reading about this subject, www.dynothane.com/downloads/EventsImpactingScoring.ppt

It's a study that tries to quantitatively measure the impact of scoring based on changes made to lanes, lane surfaces and balls. The measurement is the ratio of honor scores to the number of registered bowlers.

The study started in the 1840 time frame through 1999.

Some Measureable impact dates and cause:
1914 - Brunswick announces an aggressive research plan to introduce a new ball every 9 years
1928 - flat bottom gutters were mandatory to prevent pins from coming back onto the lane.
1936 - first 3-finger ball introduced and used by Ned Day
1938 - lacquer formula developed.
1945 - lacquer lane dressing required. All scores dropped.
1956 - Smaller diameter pin base set at 2". Scores increased.
1963 - minimum pin weight raised to 3#2oz. Scores dropped.
1972 - dry outside boards under inspection, walled shot. Scores increased
1976 - Durometer reading of 72 for all balls after the Soaker Ball was banned.
1977 - Synthetic lanes introduced. Scores increased 15%
1978 - Water based lane finish developed. Scores increased 20%
1982 - Urethane balls introduced - Scores increased.
1987 - 24" minimum lane oil rule. Scores increased 16%
1990 - 2 piece balls introduced. Scores increased 11%
1991 - Lane dressing determined to be too short. Scores increased 13%
1991 - Reactive Resin balls introduced. Scores increased 35%
1993 - Terms, RG, Diff, COF and COR were introduced to control balls. Scores increased 21%
1995 - High viscosity oil developed
1998 - Particle ball introduced with high friction. Scores increased 54%

As you can see. The increase in scores has been since 1977, and mainly due to lane surface, lane dressing and ball manufacture.