'Dynamic' whatsits are often thrown around like confetti, but Tiger Woods 09 actually deserves the term. Behind every shot you take is a four-part attribute system, based on Power, Accuracy, Short Game (chipping, etc.) and Putting. Hit the fairway every time, and your accuracy will creep up. Find the rough too often, though, and it'll come plummeting down.
And here's where the 'replay' moments come into play. The worse you play, the worse your attributes will get, and so the worse a chance you'll have to produce a good shot. So any opportunity to reverse the fall of your powers is welcome - and by going back and succeeding in the bad spots that Haney picks out, you'll recover the attribute power that you lost.
It could unbalance the game, though, since better players will simply keep on getting better. Meanwhile, poor players will suffer unless they improve. Still, life's not fair is it? And, anyway, with Haney to talk you through your problems and help you iron out the yips and mis-hits, there's no reason why you shouldn't be able to improve your game.
If, on the other hand, you've already got the skills needed to pay the PGA Tour bills you could just make the game harder - with the prospect of a powerful reward, thanks to another new aspect of Tiger Woods 09, the Club Tuner. This enables you to eke out extra yardage, loft or fade from your game-sticks, while trading off on how easy it is to hit the perfect shot.