Perhaps a thing called courage? I don't think anyone necessarily underplayed the fact that the Dark Dragon and others were dangerous per se, but were the heroes of the show supposed to just back down and cower in a corner? Of course not, that's not what makes them heroes. Plus you have to factor adrenaline into the equation -- remember when Fred and Jake encountered the DD, Fred was visibly frightened, and Jake simply did what he had to do. It's not like he could back down -- he is the AD, after all, and plus it's really not in his personality to back down from a fight. And someone's gotta battle this guy, anyway.
And the Huntsclan... well, let's be honest, they weren't really THAT formidable either. Maybe to one without magical powers, sure. But to a dragon who can, figuratively speaking, fight fire with fire? It's not a cakewalk (unless we're talking about 88 and 89) but it's certainly rarely a matter of life and death.