A multi tooth cutter in that case is no different from a single point cutter, except you have X teeth cutting in a single line, instead of a single tooth cutting a single line.
You're amount of overcut, is just the same a single point cutter, in that it depends on the relative diameters. A big diameter cutter in a relatively small hole is going to overcut more, than a small diameter cutter in a relatively big hole, regardless of the number of teeth.