Looks like all weaponskills use up IR stacks. With the exception of Primal Rend, Onslaught and Upheaval/Orogeny if Onslaught is anything to go by.

This does confirm sadly that Infuriate's Chaos attacks would indeed use up a IR stack. So Infuriate will need to be separate from IR I think.

This is probably done so the immunity to most status isn't super broken.