Walk-forward is a habit: train, seal a test window, then roll. The numbers that matter never appear in a locked preview.
Costs, borrow, and slip change the shape of an equity curve more than a headline Sharpe. Those details stay behind the account gate.
Nothing in this blurred block is the article. It exists so the page can show a body without sending the real markdown.
Market structure notes
A rolling factor window can look clean on paper and still drift when the basket changes composition. The placeholder below is decorative filler, not a research result.
Residuals are often described as leftover variance after a common move. In a real note this section would name the tickers, the window, and the exact score.
Regime filters try to keep new entries out of quiet tapes. Whether a percentile gate helps depends on the theme and the sample, not on this blurred copy.
