He estimates he has played the Raptor Course at Grayhawk Golf Club 75 times, and his last two rounds were among his best.
Oberholser shot a 6-under 64 on Friday for an 11-under 129 total and a one-stroke lead halfway through the Frys.com Open, the fifth of seven stops on the PGA Tours Fall Series.
This was my practice facility in 2002 when I first moved down here, he said. Ive played this golf course so many times and Ive been in every spot imaginable, so Im very comfortable around it, and I really have no fear of any golf shot out here.
Australian Steve Allan, who also lives in Scottsdale, shot a 63 and was one shot behind at 10 under on the sun-baked 7,125-yard desert layout.
Brad Elder and George McNeill were 9 under after 63s.
Paul Goydos ' the 2007 Sony Open champion ' sank a 47-foot birdie putt on the 18th hole to highlight an 8-under 62. Goydos was tied with Aussie Mathew Goggin, first-round co-leader John Mallinger and Robert Garrigus at 8 under.
Billy Mayfair and Steve Elkington were among five players at 7 under.
Like Oberholser, Allan, Goggin, Garrigus and Mayfair live in Scottsdale.
Kevin Stadler shot a tournament-best 61, but still missed the cut after opening with an 81.
Oberholser, a top 10 finisher 18 times on the PGA Tour heading in to this year, is playing his second tournament after coming back from two surgeries on his left wrist in a span of nine months. He said the forced time off may did him some good.
I made a decision to change teachers, and the good thing was that I hadnt been playing so I hadnt been working on any bad habits, he said.
The winner of the 2006 Pebble Beach Pro-Am, Oberholser says he had developed many bad habits while compensating for the severe pain he had felt in the wrist. He said the first surgery didnt fix the problem, but the second one ' to remove bone spurs ' did.
Its actually been a blessing in disguise, he said, because now Im coming out here with a fresh look and a fresh start.
Allan ranks 139th on the PGA Tour earnings list. A move up to the top 125 would give him full exempt status for next year.
Its nice to be playing well, he said. Theres a lot on the line at this time of year, and Im really trying hard not to think about it and just enjoy the fact that Im hitting the ball good.
Doug LaBelle II, who shared the first-round lead, shot a 72 and was six back at 5-under 135.
Also at 5-under was Richard Johnson, the Nationwide Tours leading money winner a year ago. Playing the back nine first, Johnson hit the water twice on the par-4, 515-yard 18th for a triple-bogey, then had a double-bogey on the par-4 second. He sprinkled in four birdies for a second round score of 1-over 71.
Defending champion Mike Weir followed his first-round 66 with a 68 for a 6-under 134.
Davis Love III had an eagle on the fourth hole, the courses only par-5. He was at 4-under 166.
Vaughn Taylor had a hole-in-one with a 5-iron on the par-3, 209-yard second hole but still missed the cut.