Of all the instructors I know, and have known over the years I'd say few have IR's. If they do they are very active on the market for an airline job!
I myself have a Multi-crew IR, but not a single pilot IR, so I when I instruct occaisionally it is with the IMC priveledges of my ATPL.
I agree though - if it isnt these days the IMC should be a pre-requisite for the FIC course.