When to use
- A change is risky (canon/timeline/payoff) and might break the mainline.
- Author wants to explore multiple routes in parallel.
Branching rules (simple, strict)
- Branch if:
- canon changes would require editing many existing chapters
- timeline constraints are violated and fix is non-local
- payoff plan changes the story’s core promise
Comparison checklist
- Narrative Tests: pass/fail delta
- Setup/Payoff ledger: debt ratio, broken setups
- Reader personas: confusion / payoff strength delta
- Author intent: does this branch align better with the deviation intent?
Merge strategies
- Pick winner: choose one branch entirely (fast)
- Selective merge: pick best chapters/sections (requires strong diff discipline)
- Dual timeline: keep both as alternate route (rare; only if author wants)
Output
branch_compare.md(diff summary + test/persona/ledger comparison)merge_plan.md(chosen strategy + concrete steps)