As Dedalos said, the average MA HOer will mess up its merge simply because they hold the trigger for too long.
In our case (Dedalos and I), HOer always gained an advantage, no matter the separation, because sooner or later you have to start your lead turn, which usually means you turn into an opponent and that will bring you right into his path. If you know other guy will go for HO (as it was in our case) you have to adjust your lead turn timing. You can't go for early one because you get shot, you stick with your normal, you get HOed, if you wait, you're late and at disadvantage. Even if you stick with timing but adjust your turn to be more offset, you'll lose time and with that position/angles for the next one.
Good stick won't hold the trigger until planes pass, he'll just go for brief snapshot HO, which is enough for lucky hit or to force other's guy hand. In each case, HOer gained an advantage.