Story from back in the day...Faldo was hitting new clubs with Rifle shafts with Barney Adams by his side. Nick kept going back to one club, as he wasn't hitting it like he thought he should.....tell's Barney "this isn't a 6.0 (forgot the actual flex) shaft, it's not tight enough". Barney was sure that it was, took the club back and had the shaft tested, it was .5 off of the flex that he was using. That's how tight a tolerance these guys play with.