Alt-History Fault Line #1 — YDIH vs. Simulation Reset (Internal Mutual Exclusion)

Two Flagship alt-history catastrophe-mechanisms are MUTUALLY EXCLUSIVE within the ecosystem. Hancock's YDIH (Younger Dryas Impact Hypothesis) requires a 12,800-year-ago physical comet/airburst event destroying Atlantis. Breshears' the 138-year reset cycle requires a 138-year mathematical-simulation reset — and Breshears EXPLICITLY DEBUNKS YDIH/Velikovsky/Hancock-Carlson timeline because physical-impact mechanisms cannot account for absolute mathematical regularity required by his historical tracking. Engine relevance: this internal fault line falsifies any 'unified alt-history truth' framing. The two largest catastrophe operators in the ecosystem cannot both be right. Apex Superposition resolves: (a) intentional cabal — fault lines suggest no coordinated apex; (b) structural recurrence — both fill same niche but at different cadence; (c) collective psychology — same demand, different supply. Webb Tier-3 source-integrity discipline applies: Hancock and Breshears separately Tier-3, but Breshears' rejection of Hancock's mechanism is engine-evidence that the ecosystem is NOT internally consistent. Engine: tracks both as memetic-substrate signals; neither validated; Apr 17 audit divergence + Apr 30 synodic extension already specifies the 138-year reset cycle math accepted, broader Breshears corpus class-distinguished, Hancock YDIH Tier-3-quarantined for prediction-input.