Degreeing Cam / Offset Keys available?

This Chevy key idea does not sound to me like it will make fine cam timing changes, unless you can find a 1 degree key. And even then that sounds like a problem, as the cam snout diameter is smaller than the crank snout. A given physical offset will produce an increased number of degrees change at the cam sprocket, meaning even more degrees of change at the crank.

If anyone has the actual offset dimension of either of these keys, then the actual timing change can be figured out.