Brian has the reputation as being one of the best putters on tour. Any insight on what he works on?
From the Address Position shown in these photos (which I took at the '07 Honda), Brian Gay simply makes a Paw Minor Basic Stroke. That is, his Arms are bent and frozen (Power Package zeroed-out), and his Stroke is a 'rocking' shoulders (body-only) motion imparting Angled Hinging (10-3-H). Note the Arm alignments (both Forearms On Plane), and also the Grip: Reverse Overlap with Left Hand Rolled; Right Hand Turned; and #3 Accumulator Zeroed.
I took more photos yesterday, the day before the 2009 U.S. Open, and BG's Stroke and Address position (including Centered Head, Grip, Ball Location, Hands Location, zero Shaft Lean and slightly Open Stance) haven't changed a bit. I'd post them now, but unfortunately, I left my download gear at home. I'll put'em up next week.