Yeah I've always felt like the missing part of the loop (in the context of pointing stories) is looking at point estimates and then tracking how accurate they were, _by developer_. E.g., I throw 2 points, but it turns out the story takes something along the lines of 13 points, then my estimation was pretty low and my personal "estimation multiplier" is increased. Subsequently, actual point estimations could take the estimation multiplier into effect.

Of course, this is mostly a toy idea that's fun to think about, but seems pretty untenable given that it requires keeping track of time, which most developers hate. That, and there'd no doubt be incentive to game the system by padding estimates or other shenanigans.

FogBugz used to do something of that nature. I never used it, so I'm not sure how well it worked out ultimately.