Worldlines Produce; Dilation Reports - A No-Go on Treating Consequence-Reality as Evidence of Intrinsic Dilation

Relativistic worldline differences produce real, measurable, decision-relevant physical consequences. Muons reach the ground. The traveling twin is younger at reunion. GPS clocks require correction. These consequences are facts, not appearances. They are commonly described in the language of time dilation, and the reality of the consequences is sometimes treated as evidence that the dilated frame's clock has been slowed in itself — that dilation is therefore an intrinsic property of the frame after all. This paper states a narrow no-go: the inference from consequence-reality to intrinsicness is not licensed. Every standardly cited consequence of dilation decomposes into two structural components: a worldline-internal accrual along one or more worldlines, and a between-frames registration relation describing how the accruals are reported across frames. The worldline-internal component supplies the values; the between-frames component supplies the mapping by which those values are translated into the coordinate-time language of a chosen frame. Neither component is an intrinsic dilation of any frame's clock. The consequence-from-intrinsicness inference is tempting because it tracks a sound pattern in non-relativistic settings: real consequence implies real underlying property. The pattern breaks in relativity because some real components of the explanation are not properties of single objects. Dilation is not the physical cause; it is the registration description. The physical difference is the worldline difference. What is real is the accrual, the worldline, the registration relation, and the registration events. What is not real, and not required, is a slowed clock in itself. The reality of dilation as a registration relation is fully preserved. What is denied is the further claim that the relation must be located inside one of the parties to it.