Example 01 "A' the straightness tolerance is applied to the cylinder surface (feature without size) therefore Rule #1 is applicable.
Example 01 "B" the feature control frame is associated with the size specification therefore the straightness is applied to the Feature of Size (FOS) and the tolerance is applicable to the derived center line and Rule #1 does NOT apply.
See ASME Y14.5-2009, Figure 5-2 or Figure 5-3
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