Karnak, the power of the Hispanos are fine. It's the frequency of those multiple hits at far distances which bring out the illusion of the '1-hit Hispano'.
With other cannons, you can almost count how much rounds you're hit with. Particularly with the single MG151/20 mounted on the 109s. I can count every time I've been hit with it, unless a barrage of 151/20s kill me in a split second.
But with the Hisps, it goes either "thump - kachink(parts fell off)" or "thu-thump - kachink(parts fall off)"... or, it can even be "thump - System: You have shot down by....".. when the range was like 500~600 yards, too.
Batz has once tested, and pointed out the "200 yard lag" is most likely exaggerated, and in most instances lag never causes FE differences more than 50~100 yards.
This probably means, in my layman's head, Hispanos, can hit and deal destruction to your plane so fast that the damage sounds or instant death seems to clog the rest of the 'hit' sound from playing. Whatever the reason is, the sound only gives out one 'thump', when multiple shots connect.
People begin to think a single hit has destroyed their parts off, when in truth multiple rounds hit with very short intervals.
...
But really, nobody cares whether they heard a hit sound once, twice or thrice.
The real problem is this:
People don't complain when they get hit like that when the bogey is behind you at 100 yards. That means you sucked big time, and let the Hispano armed plane get to you that close.
But people do start complaining in disbelief when they get hit like that out at 500~600 yards, slow but steady separation from the Hispano armed plane, and doing a slow jink left and right. The guy behind points, aims and pulls, and a sudden thud will hit you, and hit you bad.
Now, in that sort of a situation, how in the world did that cannon land enough hits on a same spot, to cause structural failure? From 500~600 yards away??
No wonder people call it the Hizooka.