Not to derail this thread but a more interesting question might be, "What do you do to quickly center and stay centered?"
My GPS triangle practice sessions revolve around (no pun intended) entering the thermal, centering as quickly as possible and maximizing climb rate. Leave the thermal, approach it from another angle and repeat.
I'm w/ tkallev on this, for what it's worth. If you are favoring one direction over the other, you're handicapping yourself. For me, it was hard work to break that habit but I feel much more proficient knowing that I can wrap it up in either direction -- especially close to the ground -- when the need arises. This becomes especially critical as the wing loading goes up.
Originally Posted by G Norsworthy
On the road I usually fly all the way through a thermal and out the other side before starting the turn. The way I turn to go back into it often depends on the terrain, the location of the sun, and how far off the road it is. I will take another pass all the way through the thermal at a different angle and try to mentally mark which side is stronger. Using this info I will then start the circle from where I ended up. The direction depends only on which way the perceived core is and the shortest path to it. I will only alter the direction if there is another plane in the space.
Closer to the ground I tend to fly the plane more like a dlg and keep it going the direction I start but adjust the location for drift by loosening and tightening the circle on the sides.