I still consider myself a newb...having only started playing WGT again recently...so I'm not the best source for advice in this virtual world.
But, the points made by Infinito are spot on. Having just been graduated to the Master teir (before I was ready IMO, but who is, right?), one of the first things I noticed that helped me was a different course management strategy. At the Pro level it was all about banging drives and going for every green...not the case now, or at least until I get accustomed to the game change and new clubs.
It's a new set of challenges that has refreshed the game for me. I'm sure I'll experiment with other clubs until I find my ideal fit...but look forward to the journey.
Back on topic...yes, in my opinion clubs do make a world of difference.