Valéry;5640987:(why on earth my right post should inflate my left inflator)
In the case of a runaway inflator you can shut down the right post while using your left hand on the pull dump and not cork to the surface. Left post for drysuit inflator.
It sounds as though you have a dual bladder wing though. Doesn't help you there.
Also I'd say spg on the left will indicate left post roll off or manifold accidentally left shut. A couple of 80's slung there don't really get in the way much.