Nope...That is incorrect.
He (mtnmn) stated that you need enough separation not to collide, which is a bit of humor I would think.
He implies that you have to have separation at the merge to prevent getting shot. That is demonstrably false. All you have to do to prevent getting shot at the merge is not provide the bandit a shot opportunity. That is geometry not distance. In fact, once you are inside the bandit's turn circle he CAN'T shoot you. Closer is better in this case. Maybe he doesn't know how to pass close aboard a bandit at the merge without getting shot. Maybe he does. I don't know.
I know how to do it and it is a useful tool when I want to deny the bandit turning room for a lead turn. And you want to be as close as you can when you use it because the closer you are to him when you pass the more out of position he will be if he goes angles at the merge.
It is a very big part of 2 v 1 tactics to be able to execute a merge close aboard without getting shot in the face. It is the basis for setting up most of the follow on maneuvers following an offensive split.
No, the separation I'm referring to is the space/distance between the planes, which you obviously must have. Without separation, you have a collision. Until you collide, you have separation. After you collide, and bounce or tear apart, you have separation again. Separation can be measured in miles, meters, feet, inches, whatever. Without
any separation, though, you're done fighting.
Specifically, you're describing
controlling or manipulating
the amount of separation present
at a particular point in your merge. You have separation, and you need it, you just don't want too much for the case you're describing.
And that's where things get tricky... How do you describe separation between the different planes, and at different points in the fight? If you both took off from separate fields at the same time, you'd have maybe 25 miles of separation horizontally, but little or none vertically. During a fight, separation will shrink and expand, in three dimensions. As soon as it reaches "zero" or "none", though, you're dead.
If you look back at your own post, you'll see yourself describing separation. Words like close, close, close aboard all describe distance (separation). Can you even have geometry in a fight
without distance?