When it was legal I tried anchoring (belly) and it was fantastic on shorter putts. I completely stopped pulling putts and it felt like cheating from that 4-6 foot range that I sucked at.
It was horrible for long putts on slow public course greens though. I could not get the ball to the hole with the putter anchored....at least not here in New England. Out in AZ at a high end course it wasn't an issue.
I've wondered what it might be like to have a wedge with a longer shaft that you "anchor" like the armlock putter. Would it be easier to chip/pitch the ball around the green? Would it be legal since the putter is? I don't plan on trying it, but this is the stupid stuff that runs through my mind.