Hi,
20k is still a very good altitude for a P51 and 109, the P47 start to shine good above 24k.
In that high alt dogfights are somewhat like in slow motion, its not that easy to lure someone, whi fly an advanced plane, into a mistake. Therefor, once you have someone behind you its difficult.
If Tempest, La7 or plilots with the currently faster plane run for aaa, its not that nice, cause they can gain distance and altitude without, but realy, noone can force anyone to fly into aaa, its simply stupid.
In your case, you dont had any advantage over the two oponents, if you was able to stay alive, long enough to make them greedy enough to make this mistake, i only can say WTG.
We simulate aircombat here, one main part is to stay alive. At least for me its a major aspect, if i dont would care about it and always would fight to death, even in absolut hopeless situations, i would miss big parts of the immersion.
Its also not very satisfying to have oponents, who go into a fight without a real possibility to win. I always think "what a stupid guy and what a cheap kill for me".
Greetings,
Knegel