Well, blocking should work quite well if you've got someone else to attack (like a dog) the enemy in the back. When the enemy then turns around, it's time to strike...
If you're heavily armored you should be unlucky to get bad injury when hit, and if you're heavily armored you might actually want to rest up a bit between you (counter)attacks, and if the enemy is skilled and has a weapon with a greater reach you may have a slim chance to land a strike before the enemy is has tired enough to lose some skill. In that case, blocking or dodging and backing away works fairly well at tiring the enemy: he'll soon be slower than you, at which time he'll run himself completely into the ground. Once breathless you can kill him by throwing rocks at him from the safe distance of two tiles... This assumes the enemy doesn't have a bow or crossbow: those are always dangerous.