Shift proficiencies by using different weapons?

[Gaunt]

I think instead of just picking which categories your weapon proficiencies go into they should be assigned depending on which weapons you use.

For example: My character has 145 two hand prof and none in other spots. If I start fighting with a polearm instead of a two hander, my proficiency points should start shifting to polearm.

You would not gain or lose proficiency value, but could switch where they were allotted.

[Torp]

this would be a nice way of shifting proficiencies imo, but you should have the opportunity of not switching... fighting with 150 pole prof and a 2h shouldn't mean that you start losing your pole prof, it should just allow you to turn some of them into 2h if you want to.