Screw all that nonsense and fly a 190A8 with the elephant guns package and embrace the HO!
Having said that, the HO is a great way to equalize an unequal situation. If the other guy is in a faster plane, or turns better, or has more energy or has more altitude, or has more friends nearby or is a better pilot or flies a plane with a lower ENY number, or has wing-mounted guns, then I will push for the HO.
The P-38, 190A8, Me-110 and Mosquito will usually win most HO jousts, so don't be afraid to give that attacking P-51D or Spit IX a face full of lead as he charges in. Typhoons can be a bit tricky because of the reach of their cannons, but just open up before he does so that your shells land first, then duck out of the way when the counter gets to d600 before you get within his convergence zone.
I flew Air Warrior for years and the HO was the standard salute before engaging in the real fighting. It was like having full deflector shields - you hardly ever got hit from the front. And there was no such thing as a collision, so you didn't have to worry much about losing a wing at the merge. If you fired your guns at the HO, you were just wasting ammo (or hoping for a lucky ping). As they introduced more planes with AW2 and AW3, some planes got off better with the HO than others, but it was still a widely-used practice.
Aces High changed all that. Collisions and new damage modeling required a change in tactics. But changing tactics wasn't as difficult as learning the new ballistics and flight model. Old habits are hard to break, but they can be broken. Its just a matter of whether you really need to or not. In a 190A8, or a P-38, or any other plane with big nose-mounted guns, the HO is the way to go. Its easy to shoot a non-maneuvering target and the enemy that accepts an HO makes my job easier because he flies nice and straight into my gunsight pipper. I don't have to worry about bullet travel time or deflection shooting 'cuz the target is stationary relative to where my guns are pointing.
I get a laugh when I'm in a Yak or 109 with the big 30mm gun and can tag a guy in an HO. One shot, one kill!