Where the fixed fastener formula is used, the position tolerance values result in a(n) worst-case clearance condition when the holes are at MMC and located at their extremes (virtual conditions).
In the context of geometric dimensioning and tolerancing (GD&T), when the fixed fastener formula is used with holes at their maximum material condition (MMC) and located at their extremes (virtual conditions), the position tolerance values result in a "worst-case" clearance condition.
This means that the clearance between the two features (for example, a hole and a shaft) is maximized to account for variations in size and position, ensuring that the fastener will fit under the worst possible conditions. The fixed fastener formula is a way to establish the maximum and minimum limits for the acceptable position of features in an assembly.