It's a perfectly sensible practice. It is, perhaps, an unfortunate name, since as a term of art it makes sense but the plain English implies an awful lot of val

It's a perfectly sensible practice. It is, perhaps, an unfortunate name, since as a term of art it makes sense but the plain English implies an awful lot of value judgments for what is really just a "a recognized and intentional mismatch resulting in a fudge factor".