A MARKET-NEUTRAL, two-instrument STATISTICAL-ARBITRAGE spread reversion on the two most tightly co-integrated crypto majors — BTC and ETH perps — traded at the 1-HOUR horizon where their beta-adjusted price spread MEAN-REVERTS (idiosyncratic order-flow shocks in one leg temporarily decouple the pair before cross-market arbitrageurs realign it). Construct the spread = log(ETH) − β·log(BTC), with β from a rolling regression over the trailing window; z-score the spread against its rolling mean/std. When |z| ≥ entry_z, take a DELTA-BALANCED, beta-neutral pair: if z is high (ETH rich vs BTC), SHORT ETH / LONG β-scaled BTC; if z is low, reverse. Close as the spread reverts toward the mean. This is deliberately a DIFFERENT family and OPPOSITE SIGN from the dead relative-strength / cross-sectional MOMENTUM basket (which TRENDS the alt/BTC ratio over 1D–weekly horizons and died repeatedly in the 0/84-survival beta-neutral-momentum class): momentum bets the spread PERSISTS over weeks; this bets the spread REVERTS over hours, exploiting the fact that at intraday horizons the BTC/ETH spread is dominated by mean-reversion, not drift. It is also unrelated to the funding-carry, OI-trend, and options families I have already covered. Both legs have multi-year 1H history on Binance, so walk-forward windows and the 15-day holdout populate. 3 parameters: rolling window length, entry z, exit z.