The interim USGA report of their extensive test program to determine the full scope of spin generation was sent out to manufacturers recently. In his September eTECHreport, Tom Wishon has an article commenting on it.
http://www.wishongolf.com/etechreport/2006/september/The USGA’s study is apparently comprised of five components:
1. Field Benchmark performance testing
2. Establishment of surrogates for grass
3. Face treatment performance testing
4. Study the effect of face treatment performance on shot trajectory and landing behavior
5. Confirm laboratory testing with field testing
Components #1 and 2 are completed and #3 is presently in progress. The scope of the study certainly suggests why the USGA apparently takes so long to reach a decision on these kind of tech matters. It must be complicated for instance to develop a surrogate for grass.
Among the interesting findings:
"While space limitations in the E-TECHreport limits the inclusion of the vast amount of test data compiled so far by the USGA, in a nutshell, the player and lab testing have revealed that U-groove spin rates from the rough were in the area of 40% higher for the 5- and 8-iron, and approximately 25% higher for the Sand Wedge, than for the V-groove clubheads."
"The USGA reported that it was clear from the player data that the configuration of modern club faces has significant performance improvements over the traditional V-shaped groove in grassy lies. For some lofts, it was found that spin using the U-groove club in the rough was actually higher than from a clean lie."
"While the USGA still has a lot of their total test protocol yet to complete and has not predicted a date for completion or decision making, the “word on the street” from the golf industry based on the data revealed is that golfers should expect to see the USGA ban U-grooves and either go back to only V-grooves or some other groove shape that may be “in between.”"
What's interesting is, that as a manufacturer who stands to gain by selling new $1000 sets of v-grooved irons to players who's u-grooved irons have been banned, Tom is not in favour of the ban on u-grooves. His solution to the issue is 7" rough for those weeks and those courses where the Tour plays. A length where no gouger can get it out. Seems a lot less intrusive than getting the golfing public to spend hundreds of millions to replace their iron sets. Would 7" rough offend the classic architectural preservationists?