eh, it's a single thread, so worst case it goes to pull something out and it has to say it's not available. It works well with AE, which is a much more complicated situation
like, with AE you might have a theoretical recipe that requires a block and four ingots, but you have a total of 11 ingots. The crafter would say it has that available, but when AE goes to extract from the drawers, it'll by necessity do it one item type at a time, and fail at the second type or whatever