I've never read of any formal study of this, but given that someone must have tried explaining the Capgras delusion to Capgras patients I'm going to assume it doesn't work. Why not?

Off the top of my head, that people believe what their brain tells them above any outside evidence, c.f. religious conversion originating from what, to the outside view, is clearly a personal delusion - but, from the inside view, is incontrovertible evidence of God.

It takes very good and clear thinking for the lens to actually see its flaws even when you don't have brain damage to the bit that evaluates evidence. I'm somewhat surprised a rationalist with schizophrenia actually managed this. Though TheOtherDave has mentioned being able to work out that a weird perception was almost certainly due to the stroke he was recovering from, and Eliezer mentions someone else managing it as well.