If you take ALA at the half life (3 hours) or less it doesnt redistribute much at all, because the mercury that wasn't excreted binds with the new dose of ALA. This is why Andy say it will take 30-40% longer to recover if you use only ALA, because you do excrete less every round compared to ALA + DMSA.

The figures were from this study
http://findarticles.com/p/articles/mi_m0FDN/is_6_7/ai_96416600

Its in there somewhere...at least I'm pretty sure it is.