Before he died? If he did, then it wasn't really a flashback, but more of a "life flashing before your eyes" kinda thing. Not even close to what's going on with Kabuto. The only kinda flashbacks I remember for Gaara were to him hearing about the Sand's coming invasion of the Leaf, him being betrayed by his uncle and deciding he was only meant to kill, and to his birth (which I don't believe was even his flashback).
Well, it just came back to recent times and showed us how he got to his present form, so this should start picking back up by tommorrowkomment are only on 17 pages... it shows, that the last chapters arent so exciting
i have no problem with the flashbacks, but i think, these informations should take less place
its a bit boring for more than 3 chapters:/
we will see, what is it good for