Dueling is pretty silly, in my estimation.
Most fights did not begin at co-alt with "fair and even" speeds and conditions. Air combat (even 1-vs.-1) is not a joust, or an effeminate Elizabethan "affair of honor" with antique pistols and "seconds" standing by with the oak boxes they came in.
You started the fight based on any number of other mission variables. Sometimes you started with an advantage, sometimes not. You just played the hand you were dealt and survived by your skill and your SA and sometimes by your technological superiority.
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Now, that said, if you're going to duel, it is all about knowing your capabilities vs. the enemy's and exploiting it. If you find you just can't get angles or you're always being
quickly out-manevered, my guess is you're pulling way too hard on the stick right after the merge and bleeding energy, while your opponent is tightly abiding by his corner speeds and getting more out of his E than you are. That, and he may simply have better-honed situational awareness skills than you.
Never underestimate the power of a simply keeping (or storing) energy against an aggressive dueling opponent who will try to solve the issue immediately. Just after the (guns off) merge, go into a straight ahead,
but gradual pitchback maneuver and watch as best you can what your opponent is doing back there as you climb out. If he turns hard or dives, you should be getting an alt advantage that should win you the fight by itself. If he climbs along with you, then it truly becomes an energy duel. (of course, if you're dueling in dissimilar planes, and the enemy's plane climbs a LOT better than yours, the above isn't likely to work, since his climb advantage might nullify your pitchback even if he does waste some energy in turning)
Once you have a decent alt advantage and some horizontal separation, then turn back (
gradually, not in one blackout-inducing 6-G turn
) watching your enemy the whole time. Try to get him to go nose up to come after you. If he does that, you can go nose up, too, draining both of you of energy, and eventually, he's got to drop his nose before you do, and at that point you can drop down on him and either gun his brains out, or do a feint to get him to blow even more energy in break turns or barrel rolls.
If you don't have any climb advantage, and the pitchback won't help, you might try to simply dodge your opponent until he makes a critical mistake. Just loiter about and watch him, and dodge gun passes with break turns, dives or whatever you need to survive. The goal is to get him to commit to a gun pass where he dives well below you.... you pull up into this, dodge the pass, and you then have an alt advantage to turn the tables.
If opponent's very patient, or a veteran boom-and-zoomer, then you won't win with this strategy. Eventually, he'll force you to trade alt for speed needed to dodge his attacks... and he'll get you sooner or later... unless you can force that one mistake.