I agree that's probably a metal chip stuck between them (I didn't realize a picture of in process blanks was going to be closely scrutinized, I'll have to keep that in mind), but long skinny pieces like this do move around some during grinding and machining and even more during heat treat. They get fixtured flat for machining operations and also during tempers. We never try to straighten a piece by bending it past yield and letting it spring back, we utilize fixturing and shims during the final steps of the heat treat process to get it within a flatness tolerance, which is measured on a granite surface plate with feeler gauges.
My point being, that piece probably isn't particularly bent, but if you look closely, none of it is flat (yet)