The requirement to see some piece of the surface when flying under VFR applies to UK issued PPLs (post-JAA only, I think) unless accompanied by an IMCR or an IR.
We know what you mean. But it's worth emphasising (having met this with people hour building!) that merely having someone appropriately qualified on board doesn't give the PIC anything extra. Either the PIC has to be appropriately qualified or someone else has to be PIC. All the more reason to bring in a simplified IR asap, we could even call it an IMC Rating!