Don't think you are going to get too much support for that one!!!
If you are flight planned into LHR and then lose communication at least ATC know your planned intentions, will expect you to follow published procedure for Radio Failure and continue to LHR. If you decide to clear off to EGSS you are, in the current climate, likely to find a couple of Tornado's coming up to see you! Not to mention the additional ATC load you would cause whilst everyone watches to see what you are up to and have to communicate from sector to sector just to keep everything else out of the way. (And should you think of dropping to low level to avoid radar then you will certainly become the immediate property of the Tornado's!
).