To be fair, it's whoever wants it the most. If you really wanna do the damage, and you've got your witts about you, so its controlled, you've god the edge. If you're on the backfoot, not wanting to be in the fight, you're likely to take the beating. Which is why I tell myself, if I ever get attacked in the street, I won't block, and back up and back up ... I'll anticipate the first strike if possible, block and counter at the same time as quickly as possible, and keep swinging till they're out of commision.
You see so many vids on tele on crime programs of someone getting beaten, and it's always the same. They try to block the attack - get their head down, back up, step away, and inevitably the attacker keeps coming. So my motto, back away, but when that first strike comes in, move forward, block and hit the bastard hard - preferably somewhere nasty like the throat. And dont stop till you know you can get away without being persued.
I dont have the benefit of martial arts training, but seeing as I'm mostly like to be attacked when someone is pissed, and I'm semi-drunk, with dutch courage, but in control of my faculties, I reckon it might work. Either way, I'd get a kicking, so might as well be ready to attempt to lay em out.