For things like the new Allagan desynths which come from Coil 1 equipment (Which I've got plenty of sitting in my retainer storage) you're basically at the mercy of the crafters themselves carrying enough/being able to clear this content to keep the supply going . I was able to procure all the necessary items for the i110 crafted DoW/DoM sets except for these within the day of the patch hitting.
I'm sure the common response to this is going to be "Level up a crafter and do it yourself" but couldn't you say the same thing about materia? All it does is open up an avenue for people like me who don't have access to the direct resource (ie, I cannot go into T5, scoop up the drops and convert them into what I want by myself) but I do have an excess of the indirect resource (The gear that this stuff comes from). Instead of having to level up crafting for this one particular item that I'm trying to acquire I could just pay someone (In whatever trade-able method you choose) to do it for me. The only difference is you're no longer dependent on someone else going out there and getting the materials for you, you're the one supplying the materials instead.
This also removes any possibility of just giving someone a weapon, they could still have the raid gear be "un-tradable" (ie you can't just hand someone a raid weapon) but you can give them a tool to break-down instead.