924 — The Common Coarsening Has Zero Ordinary Coefficient
Legitimate carrier span
Entry 922 proves that the diagonal and off-diagonal maximal flags have no common refinement. They do have a common coarsening obtained by deleting their incompatible middle cuts:
In both ordered flags the deleted cut occupies slot one, so the simplicial incidence signs agree:
This is the first carrier-typed span between the two branches.
Source-normalized coefficient on the coarsening
Use the frozen normalized transition
The common face is reached by
while retaining the middle-channel variables as tangential data.
The exact two-order audit gives
All twelve matrix entries vanish. Thus
Consequence for the span
At ordinary grade the coefficient-enhanced carrier span is therefore
The two incidence maps exist at carrier level, with matching signs, but their ordinary coefficient targets vanish. They induce no comparison or cancellation between the two rank-one higher-normal objects.
This explains why the lines can both arise over the same coarsening while remaining independent: they are distinct normal derivatives of a zero ordinary coefficient, in incompatible middle-channel directions.
Narrow conclusion
The first legitimate deletion span is typed but coefficient-trivial:
No new carrier cell or mixed differential is required. Conversely, the vanishing target does not prove that all higher coherence vanishes.
Next falsifier
Compute the first nonzero multigraded normal module of (widehat T_3) over (F_0), preserving separately the labelled (x), (y), and (z) directions. Test whether the carrier deletion maps induce a Koszul relation among those grades. Only such a relation could couple the diagonal and off-diagonal lines without introducing an incompatible carrier stratum.