Considering the average golfer doesn't break 100, not to mention 90, I would say shooting around par isn't only decent, but incredible. Fact is most PGA Tour players shoot "around par". What is the Tour's scoring average? Bet it's right around 72.
Breaking 80 puts you where? Not sure about the exact number, but something like the best 10% of all golfers I think. If you play golf occasionally and have another career (the Whippy inventor is a doctor), then shooting around par is great. If you think Tiger Woods is the "average golfer", you are quite off base. Do you even understand what "decent" means? What must you do, in your opinion, to be decent? Shoot 65? Wouldn't that put you at expert? Calling a scratch player "decent" is actually quite an understatement.
Also, several pros use the Whippy training aid. I know Vijay for sure and the inventor e-mailed me a list of 5 or 6 long drive competitors who do. I wish I still had it, but I deleted it. All of them bought thier own club as well, it wasn't given to them. Vijay has an entire set.