One of the group I play with came up with a unique interpretation of how Shields and the Ambidexterity card work together, and I can't find an explicitly worded point in the rules to prove what I see as the proper usage.
It is my contention that an item which requires exhaustion to take effect is only in use at the point when you exhaust it, thereby allowing your shield to absorb one extra wound level when you apply it. It is his counter-contention that merely equipping the shield counts as using it, therefore whenever you have the shield equipped, you get a free point of armor from having the Ambidexterity card.
Unfortunately, there is not a clear and explicit statement of what is considered using an item in the rules, so he and I still go around on the issue. Can any one point me to an FAQ or rules point where this can be cleared up without any further grey area?