Speaking of WTO legal claims that are a bit of a stretch (which I feel like I've been offering quite a bit of recently) ...
Typically, the "benefits" at issue in a non-violation claim are those resulting from a trading partner's tariff concessions. So, for example, when one country makes a concession on a product, other countries benefit because their exports of the product can now be sold there at lower prices.
But are there benefits that accrue to the conceding country itself from making tariff concessions, and could these benefits provide the basis for a non-violation claim? What I have in mind specifically as a benefit is lower import prices. When you cut tariffs, prices for the imported products in question are likely to fall. For non-violation purposes the question would then be, could the benefit of these lower prices be undermined by actions of your trading partners, and therefore lead to nullification or impairment?
The reason I thought of all this was OPEC. Is there an argument that OPEC's actions to restrict oil supply, which presumably raises prices, undermine the benefits of tariff concessions (and the hoped for lower prices) on oil? (Assuming there are any concessions. I haven't checked).