SOB,
Yep, this a dangerous, but tried and true way to kill.
A "hammerhead" here is rarely what is actually done. Most folks refer to any near-stall speed reversal at the top of a vertical zoom. Technically a hammerhead is where you zoom vertically until you hit nearly 0 airspeed, then hold it straight and kick rudder to reverse in a slide as you start falling again. Done right, you just spin the plane as you fall back down and then blast away at whoever is below you. Personally, I don't do a "correct" hammerhead. I normally will zoom vertically until about 50 mph, then pull back hard with elevator and kinda flop over. You may need some flap out to accomplish this.
Normally though, you don't want to have to flop at that low of a speed. Ideally, you will get the other guy to follow you up so that you can simply loop over the top at 150 or so. That way, you can simply hang inverted and wait for him to stall below you so you can drop down at the right moment and blast him.
It takes timing and skill to do properly. You also need to be a good judge of energy states, and be certain there are no enemy planes with superior energy near by who can shoot you when you are slow at the top of your zoom. You must also be aware of performance differences in the different planes, so you have an idea how long the other guy can hang there before he flops over and presents himself as an easy target. You need to set it up so that he is just out of guns range while he can point at you, and dive down just as he can't keep his nose up. It's tricky but very rewarding.

Now, what do you do if you are the lower/slower bogey, and ole Lephturn just blew past in his Jug and zoomed looking for the rope-a-dope? Easy, you play possum. Cit is the best I've seen at this. Basically, conserver your E and 0G dive whenever possible. You may have to avoid a few passes before you are ready for this. Now when the BnZ guy makes his pass and zooms, follow him up with a very gentle pull up, but try to cut the angle. Done right, you will zoom with him and close on him as he slows. Now comes the sneaky part! Nose over gently at 0G and pretend you are stalling and going back down. If it works, the attacker at the top will pull over the top and dive on you. If you have saved enough speed, pull your nose back up and blast him! At this point you have a couple of things going for you, surprise and airspeed. He is going to be surprised, and not expecting this. Also, the enemy will be slow having just reversed vertically at very low speed, and won't have very good directional control. If you can, shoot him in the face. Better still, avoid the head-on shot and reverse as he overshoots below you. Even if you don't kill him, you have just turned the tables on the BnZer and grabbed the advantage.
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Sean "Lephturn" Conrad - Aces High Chief Trainer
A proud member of the mighty Flying Pigs
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