The path the estimate runs along
§4 slab transfer, §8 affine-path regularity — and the mechanism U_GJS is
imported at
What is happening
To compare ωg with ωg′ the manuscript does not jump between
them. It joins them by the straight line
gs = (1−s)g + s g′, s ∈ [0,1], differentiates the state along it
(Lemma 10.1), and integrates the derivative. That is why the estimate is called a
one-path estimate.
The path has to stay in the class for this to mean anything, and it does:
0 ≤ gs ≤ 1 pointwise because the constraint is convex, and the support is
contained in the union of the two supports, so it stays compact. That is Lemma 3.1.
This is also where U_GJS lives. The source proves its Theorem 1.1.1 along
exactly this construction — the affine path h₁ + α(h₂ − h₁) between two arbitrary
cutoffs of its class — and applies its Theorem 1.1.7 at every cutoff of that
path with one h-independent constant. The cutoff-uniform quantifier the manuscript
imports as A8(vi) is the one the printed proof uses here, which is what the scope
amendment of 5 September 2026 records.
The passages are quoted verbatim in A8(vii′); see
imports.