The simple answer is yes.

For each point that your weapon skill exceeds your opponent's defense, you gain the following:

* Your chance to miss decreases by 0.04%.
* Your chance to score a critical hit increases by 0.04%.
* Your opponent's chance to block your attack decreases by 0.04%.
* Your opponent's chance to parry your attack decreases by 0.04%.
* Your opponent's chance to dodge your attack decreases by 0.04%.

The values shown on your character page assume that your weapon skill is equal to your opponent's defense rating (or rather that you are both the same level with max weapon skill and def rating respectively). So if you have been using a weapon of one type and switch to another with a lower current skill rating, your crit chance will decrease by a value of the rating difference * 0.04%