I bought a DeltaZ Osprey with the maple red handles, but the blade has what appears to be lots of little air bubbles in them (sorry, I don't know the technical term for it). It's concentrated mostly towards the back of the blade (is that called the tang?) and around the thumbhole area. Does this affect the strength of the blade, or is it an indication of a poor job? The steel used is Z60CDV14 Swedish stainless.