**Chain split guidance, restated without the team colours.**
Call them the enforcing chain and the unrestricted chain.
**There is no split to transa...
**Chain split guidance, restated without the team colours.**
Call them the enforcing chain and the unrestricted chain.
**There is no split to transact on for a long time.** Mandatory signalling constrains block headers, not transactions. The reduced data rules bind at height 965,664, which a minority branch reaches slowly. At 20% hash that is about 20 weeks after the window opens, at current signalling over a year. Until then every transaction, giant OP_RETURNs included, is valid on both branches. Splitting coins via OP_RETURN is impossible before the enforcing branch itself reaches activation height.
**Replay protection must be built.** Branch-exclusive coins come from two sources. Passive: post-split coinbases, spendable after 100 blocks, within a day at 97% hash, three weeks at 3%. Active: RBF from the first divergent block. Get confirmed on one branch, then bump. The original's outputs are now exclusive to one branch, the replacement's to the other, and every descendant inherits the split. No maturity wait, though at 3% hash the slow branch's next block averages five hours out, and the bump must not reach the fast branch before the original confirms there. Until you hold and spend such a coin, your payment confirms wherever it gets mined, or on both branches.
**"RBF or CPFP" is half wrong.** A CPFP child spends a parent that exists on both branches, so it replays and pays both miner sets. It signals nothing. An RBF replacement of a transaction already confirmed on the other branch conflicts with a confirmed transaction there and can only ever pay the branch where the original is still pending. RBF is the only tool that creates branch-exclusive fee demand, and it works in both directions.
**Fees follow prices, not the other way.** All miner revenue lands in a branch-exclusive coinbase worth whatever the market thinks that branch's survival is worth. With shared difficulty, revenue per hash is price times block reward. Grant equal prices and the mechanism in the original actually works, and needs no RBF: everything replays, so the minority branch's mempool holds the majority chain's entire confirmed history as backlog, its blocks skim the top by feerate, and its fee per block is higher until hashrate reaches parity. But equal prices with 1 to 3% signalling two weeks before the window is not an assumption, it is the conclusion smuggled in as one. Fees run at low single digits of the 3.125 BTC subsidy. At a 20% price ratio an enforcing block needs over 12 BTC in sustained fees just to break even. The mechanism is real and two orders of magnitude too small.
**Parity is the starting line, not the finish.** Non-enforcing nodes reorg onto the enforcing branch only if it takes the cumulative work lead. Every day at 20% hash digs 0.6 network-days of deficit. A week at 20% costs three weeks at 60% to repay. And a branch whose block production runs through one or two pools is one DoS away from stalling, while futures markets set the decisive price ratio before the window even opens, and against a 3% branch, rented hash is cheap griefing. The reverse risk is simpler: miners abandon the enforcing branch and its coinbases go to zero, no coordination required.
**What survives from the original.** Decide which branch you are on, run a node that enforces your choice, and do not treat a confirmation on one branch as a confirmation on the other.
