Position on Bolt Hole Diameters

In this Question Line video, Jason explains what the position callout is controlling when the feature control frame is attached to a hole within a bolt hole pattern.
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[@saagusaagu]

Which means we don’t need to verify the bolt circle diameter as long as the basic dim is located. All we are concerned is about the position of individual 8holes. I have one question though, If one of the hole is inspected and measured a dia of .254. What would be the additional tolerance allowed for that hole?

[@Gdandtbasics]

Your first statement is absolutely correct, we never actually measure the bolt circle diameter. We simply check each instance and its location which indirectly controls the bolt circle diameter. To answer your second question, since the MMC modifier is NOT present we don't get any additional tolerance. However if it WERE present we would get an additional .009 of position to add to the existing .005 resulting in a total diametric position for that single hole of .014 inches.

[@brianbontrager7618]

The 8 holes would need to be a simultaneous requirement output per ASME 14.5 right? Would software treat them more as a single pattern instead of separate features if output as a SIM. REQT.? Would the results really be any different?

[@Gdandtbasics]

The 8 holes would definitely meet the simultaneous requirements applied by default via ASME Y14.5. Ideally the software treats anything with the same datum structure as SIM REQ by default but this is not always the case for all software.