more Labour voters around LHR cp LGW
And that's why Gatwick is more acceptable, and HS2 is going ahead.
Q: If surrounded by a sea of safe blue seats, what is the worst that can happen?
A: They become slightly less safe.
LHR is a surrounded by a sea of marginals, all colours are represented, so a hell of a lot to lose by building a new runway.
Foster Island is also surrounded by blue, although Cliffe was Labour in 2003. My thinking at the time, and ditto for Rugby was:
Take one marginal seat, propose something outrageous, and then make a hero out of the local MP(s) for 'saving' their constituents for the David v Goliath battle, in which Goliath had no plans to actually turn up.
The reality was that Rugby, Warwick & Leamington (adjacent) and Cliffe have all gone from red to blue, so that particular cunning plan, if it was intended wasn't actually that cunning.