IIRC there was indeed a problem with that sort of thing; procs in IO sets (chance to stun ones were mentioned most often) would hit the owner rather than the mobs, leading to amusing (but not very desirable) situations where toons were knocking themselves senseless.
The "fix" for this was to make Taunt sets unslottable in taunt auras, and to the best of my knowledge a proper fix is still unimplemented. And without an ETA. 
Pretty sure that there was an issue with taunt invention sets not working in auras - think it was something like the auras saw the character and not the enemies as the target so taunt and procs didn't work.
I've had a quick look and didn't seem to spot anything definitive about this, so does anyone know:
Is this sorted out now?
Can taunt IO sets (or other IO sets) be slotted in taunting auras and get the expected beneficial outcome?
Is my memory just tricking me and there never was a problem?
Thanks in advance,
JD
(owner of a stone tank who wants desperately to get some +recharge in his mudpots...)
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