Stenson started the year in excellent form with three top-eight finishes in his first four events, but then missed four cuts in succession before a tie for 16th in the Players Championship at Sawgrass.
The 41-year-old Swede admits he is still not firing on all cylinders as he prepares for one of the European Tour's biggest events, but made the trip to Wentworth after reliving some of the memories of his stunning Open win at Royal Troon.
"It was great to be back there," Stenson said. "A lot of the memories come back to you. Even though it's recent, it's still almost a year ago, but being there for a couple of hours yesterday and seeing the scene of the crime again, it was good times.
"I haven't been that happy with my long game in particular over the past couple of months, or even longer than that. It's a work in progress, but overall I don't think we're in a bad spot and it will be nice to pick up some form this week.
"I wouldn't say we're 100 per cent but we're heading in the right direction. I'm hitting more good shots and the bad ones are hopefully a little closer to where they need to be, as well.
"I had a great year last year and always there's a bit of a risk of running out of steam at some point. I kind of did that in '14 after the great year I had in '13."
Stenson is making just his second start in the BMW PGA Championship in the last seven years, the world number five being one of many players who were unhappy with the condition of the greens at Wentworth.
An extensive renovation programme began just eight days after Chris Wood's victory last year, with four greens completely reconstructed and another five partially rebuilt, while a sub-air system as used at Augusta National was also installed.
All of the bunkers were redesigned and a total of 29 removed, with the first event of the Rolex Series also boasting an increased prize fund of £5.4million.
"It's good," Stenson said of the changes. "Some of the bunkers that were very penal before are now more playable. The greens are rolling nicely. It's not super quick, but it's rolling nicely and good greens to putt on.
"In terms of how the course plays, I don't think it plays that much different compared to before in terms of strategy, what clubs I'm hitting and where I'm trying to leave it off the tee and into the greens. That strategy of fairways and greens is going to pay off again I think."
