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Two gaps a reader could name without running anything: costs appeared on one workload out of four, and nothing in the suite was a portfolio. Costs could not simply be switched on across the board, and the reason is measured. On FractionOfEquity sizing a 5 bps fee puts the engines 1.3e-4 of capital apart and 2 bps of slippage 2.1e-5, against a 1e-9 tolerance, while the round-trip counts stay identical: the trading agrees, the cost arithmetic does not, because one charges the fee on top of the notional and the other reserves it out of cash first. In fixed units both land exactly, to 1e-15. So `sma_cross_costs` carries a fee and slippage on the headline signal, sized in units, and the price of that is visible rather than hidden: x48.0 against x50.6 at 100k bars. `multi_asset` runs five independent series in one shared book. It is the workload manifoldbt does worst on, and it is here for that reason: going from one asset to five costs it 6.1x and vectorbt 1.4x, so the ratio falls from x36.7 to x8.8 at a million bars. Broadcasting a column per asset is close to free; walking five books is not. A portfolio is also what people actually run, and a suite that only measures where it wins is not evidence. Both are capped where a materialised five-column simulation would stop measuring the engine and start measuring the swap file, and `ema_rsi_fees` keeps the ceiling it got for going bankrupt. Repetitions go from two to three: the floor at which a median is a median rather than the mean of two.