Make materia inlaying a NPC action, not a crafter action

[Peregrine]

This needn't be the only solution.

As I posted in the materia thread, if there is high-value materia for crafter-only use (e.g. +2 control, adds extra action, etc), then crafter become end-product consumers of these items.

If crafters cannot add AP to items and create these materia, then the prices of these materia will reach truly astronomical proportions. Crafters, with their large gil reserves, will be competing for these items, and the costs will not be passed back to anyone (except indirectly, in the same way as ANY class archetype).

Does this break somewhere?

There's already a situation like that. The price of HQ crafting tools is less than that of battle weapons, even though crafters are richer than battlers. There are fewer crafters, who need fewer tools. They get their own HQ products for cheap, and can charge you whatever they want for your HQ.

I'm a crafter. I know all these things. This would be a deal I would try to hide from everyone if I was interested in grubbing gil.

Whatever crafter tries to tell you that them paying for crafting materia would make up for everything is lying through their teeth.