HO is valid as a tactic in everyway, except that it's essentially a suicidal move rather than a tactic.
A gung-ho HO attack is not a "tactic".
A 'tactic', is a series of preplanned initiatives which purpose is to let you win without getting hurt. In an air-to-air engagement, a Pyrric victory would be useless were it in real life.
The only reason HO can be considered a favorable move for many people is because us gamers don't have to worry about dying. Oh, real life pilots certainly won't refrain from shooting if they ever fall into a HO situation, but it's a situation they would try to avoid in the first place.
That being said, people who rely heavily on HO is basically frustrating to fight against. There's a basic sense of logic underlying in the whole theme of ACM and A2A combat, and those who go gung-ho is basically outside that logic.
So, it's sort of like this;
".. hmm, there he comes to HO again, I'll avoid it." ..... then... "hmm.. now, I don't think he's that stupid to try it again.. so I'll prepare something else, as he probably won't do it...".... but.... "oh geez, he's doing it again... ! Have to git out of the way....".... and again, .... "he won't do it for a third time, would he....?" .... but.. "woops, there it is.. the third HO coming.." .....
Now, it isn't really hard to shoot the guy down once you realize that his mindset is basically at the same level of a charging rhino.. but before you get that, it's quite frustrating and baffling to fight someone like that.