ben, please confirm you are not "locking in profit" to do that you must exit the market. What you are doing is doubling your account risk on the largely incorrect assumption that because (as an example) NZDUSD and AUDUSD are correlated you are hedging.
In any case, all of your theory ONLY applies if you are playing the game with no SL at all. Otherwise it is entirely possible for one of your SL to get hit, market reverse and hit your other SL.
In any case, all of your theory ONLY applies if you are playing the game with no SL at all. Otherwise it is entirely possible for one of your SL to get hit, market reverse and hit your other SL.