Remembering improvisational modifiers

In order to keep consistency over the long run, I think that the players should keep track of some of their improvisational modifier. I don't talk about modifiers that depned on circumstances (which are changing by nature), but for modifiers such as using alternative weapons.

For example, a guy with sword and shield as skill would probably have the following modifiers :
-3 for using axe and shield, or sword only
-5 for using axe only
-10 (?) for using two-handed axe

If, in a later contest, the charater wants to use same alternative weapon, he should get the same modifiers (other specific circumstances modifiers may change that further, but at a starting point, I don't see why it should be different). So the player (the Narrator having enough things to do !) must keep trak of it ?

Or a list of more detailed modifiers in this case (as per my above tentative) could be useful ?

Alain.
Gloranthan Wars at http://www.karamo.btinternet.co.uk