Given the amount of mats locked up in untradeable items some sort of desynth request is really needed, perhaps with a fee structure or something attached. It makes no sense that crafters should need to be the person to get an item in order to desynth, and locks many people out of desynthesis who prefer to run dungeons. The chance / risk factor can be sorted by simply allowing the customer to withdraw after seeing the chance for the request item - I don't see any problem there.