From what I am to understand, you are talking about not diving down w/ your opponent, keeping your alt, and merging down on to your opponent.
I can't really think of a good reason to do a merge like this, and quite a few reasons not to.
My best advice is to grab a Trainer, or a good "stick" who knows what's what and try it out.
The only reason to do what you suggested (that I could think of) would be to try and create and energy imbalance and E fight your opponent.
As they come up you nose down, maybe give them a shot and try to get them to bleed Energy, and then nose back up again and try to get position on them because they blew their advantage going for that shot.
That works in the LW, but vs. a decent duelist you gonna die.
From a positional perspective the lower pilot has more options if you decide to mix it up like that. If they fly smart and don't do anything "stupid" they should hold most all the cards in the fight.