oversized pistons - general question

[dbdevkc]

I am looking at specs given by wiseco for their shovel pistons, and they list the bore size. For example:
4012P4 (.040 over) = 3.477. At what point, or what current bore measurement would it be "wise" (pun intended) to go up to the next size (.050 over) and bore the cylinders to fit?

[JW113]

Well if you believe TFM, when the piston to bore fit is greater than .005".

-JW