This skill affects combat with big blunt weapons such as war hammers, battle maces and mauls. It is also used in the pound command which uses these weapons. This skill is useful for the special commands such as pound, cleave, hack, thump and rush. This must be raised to level 5 before the appropriate sub-skills can be raised. Well, no understanding of them, anyway.
Dexterity helps to avoid hits and intelligence helps to execute special commands and skills.
These were drawn on a piece of bark and left at the bar a few hundred years ago and have been viewed with awe by barbarians ever since. Perhaps it's best to make up your own mind these days.