Two Hammer Straightening

This topic came to mind while making some long shank shoe spoons.  After fullering the blade some of the pieces had a slight offset of the blade-shank junction.  The shoulder was asymmetrical.  If the offset is not too extreme it is easily fixed by clamping the shank in the vise right at the shoulder leaving the blade extending beyond the vise jaws.  The neck-shaft junction is heated and the blade tip cooled...A heavy hammer is placed against the tip of the blade and a light hammer is used to tap the long-side shoulder until it is centered.

I first thought of this as a second class lever technique but now I’m not sure how is is properly described in mechanical engineering terms.  I do like the way it works.