There is a particular class of error that almost every reasoning system produces and almost no reasoning system catches. Each sub-result is correct in isolation. The composition of the sub-results is wrong, because a domain restriction was dropped at the join, a unit was implicitly converted, a sign convention was reversed, or a boundary case was assumed away. The output looks coherent because each piece is coherent. The composition layer is the hidden defect.
Quantm's resolution stage records each sub-result with its domain of validity attached. Composition is not a free operation; it is a typed merge that fails at compile time if the domains are incompatible, the units do not align, or a boundary assumption made downstream contradicts an assumption made upstream. This is more discipline than most engines impose, and it is the only discipline that catches the composition class of error before it reaches the output.
The deeper consequence is that a Quantm derivation cannot be debugged by checking individual sub-results in isolation. Each sub-result is correct by construction; the interesting failure surface is the merge itself. The audit trail therefore records not just what was computed at each node, but what was merged at each edge, and under what assumptions the merge was permitted. When something goes wrong, the diagnostic points to the edge, not the node — which is the right place to look, because that is where the error actually lives.