Why would the thickness at the site of a removed bulge be thinner than the original thickness? If the metal is ever so slowly put back into place by peening over a snug fitting plug mandrel wouldn't the metal flow back to where it was originally? If not, where would it go?

I'm just a layman trying to better understand this. I have removed most of a bulge by light peening, and dents as well. I probably won't mess with bulges on a double anymore, dents are no big deal, IMO.

Stan

May God bless America and those who defend her.