Order Blocks Under Strict Definitions: What a Mechanical Test Needs

[FXS Prop Desk]

Order blocks are easy to find in hindsight and hard to test, because most descriptions leave room for interpretation. A mechanical test needs every choice written down.

Decisions a test must fix:

• Which candle: the last opposite-colour candle before the impulse, or the last few candles?
• Impulse size: a minimum move after the candle, e.g. 2 × ATR within 5 bars.
• Structure break: must the impulse break a prior swing? Which swing size counts?
• Zone: candle body or full range including wicks?
• Validity: how many bars until the zone expires, and is it void after the first touch?
• Entry and stop: edge or midpoint of the zone; stop beyond the far side plus a buffer.

Once these are fixed, results can be compared across pairs and sessions. In practice, small changes to the definition often change results more than anything else, which is itself useful information about how robust the concept is for you.

If you trade order blocks, which definition do you use, and have you tested it mechanically?

[Shadow Trader]

My mechanical order block test only kept the last opposite colour candle before a move of at least 1.5 times M15 ATR within six bars. Anything looser produced so many zones that the backtest was just curve fitting noise.

Zone as full wick range beat body only on EURUSD London, but failed on GBPJPY where wicks are huge. I now fix body for majors and full range for yen crosses, written in the test config so I cannot switch mid run.

Validity after first touch is the rule that hurt my live results most. Keeping a zone live for three touches looked great in sample and terrible forward.

Stop beyond the far side plus 0.3 ATR was more stable than a fixed pip buffer. Fixed buffers ignored volatility regimes and inflated my stop out rate in quiet weeks.

Have you locked impulse size and validity before you trust a win rate, or are you still iterating those two live? I freeze both for a full 200 trade block before changing anything.