AOPA(UK) considers that the limited IFR privileges of the EIR can be adequately assessed by an FE(A) who holds an IRI(A) certificate and do not require specific assessment by an IRE(A).
The problem with the EIR is that you cannot instruct/examine for a rating which you don't hold. There are a lot of instructors using IMC privileges, without the need for a IR (SPA).
I agree that these privileges should be contained within the FE (A). However, a FE (A) with a IR (R) / IMC will not hold the privileges to instruct/examine for the EIR in any case - they will need either a IR (SPA) or a EIR themselves (!).