Why the same setup works on EURUSD and falls apart on GBPJPY

[Amanhasnoname]

A common experience: a pullback entry with a tidy backtest on EURUSD gets copied to GBPJPY and bleeds. People blame the strategy, but the strategy did not change. The market structure did.

EURUSD is among the deepest books in the world. Price tends to move in smaller, more orderly steps, and levels often get respected. GBPJPY is a cross with wider spreads, and its moves are bigger and more jumpy. It can travel twenty pips in a few seconds and gap through a stop with slippage. A 6 pip stop that is sensible on one is inside the normal noise of the other.

Three things need re-fitting rather than copying:

- Stop and target distances, scaled to the pair's own average range
- Entry method, because pullbacks are shallower and faster on volatile crosses
- Position size, since the same pip stop carries different risk in money terms because of different pip values

Even after scaling, slippage and spread variability mean the live result can be noticeably worse than a backtest. Treat each pair as its own strategy and validate it separately, on its own data, at its own times of day.

Have you managed to port a setup between a major and a volatile cross, and what exactly had to change?