MA Crossover Optimization: Separate the Cross from Confirmation

A bullish crossover occurs when the fast average moves above the slow average after being at or below it. Remaining above on later bars is a state, not a new crossover. This distinction matters when a strategy asks for confirmation: requiring a fresh bullish cross on every consecutive bar is not the same as requiring the fast average to remain above the slow one.

Define the trading policy before tuning lengths. A bearish cross might close a long position, open a short, or reverse the position; those choices produce different exposure and costs. Also state whether signals use completed bars, when orders are created and how repeated signals are handled while a position is open. A pair of plotted averages alone is not a backtest.

SMA, EMA and WMA apply different weights to price history. Fix the source and whether both lines share the same averaging type. Keep the fast length below the slow length when that ordering is part of the strategy definition. Names such as fast and slow do not enforce the constraint, and a full Cartesian grid can include equal or reversed lengths unless you exclude them.