It certainly can be problematic for a number of different reasons. Personally I think it is really important an officer retains overall control of any procurement exercise whilst sometimes they actively welcome input particularly if they know a Cllr has expertise in the area or contacts. I know a few years back the retired Policeman within our Council was absolutely superb helping put together the CCTV Tender Documents & attended the site visits with him as knew what to ask and how to ask it. The Clerk was incredibly grateful and they worked as a team... Its a balance for sure and depends how exactly its been done.