Find this surprising: not the LGW part, the SVO part!
I think the point is that they pretty much know they aren't going to win the frequencies in the scarce capacity hearing. Neither the UK (nor, for what it is worth, the Russians) are going to like the thought of all allowable London-Moscow frequencies falling into the hands of BA. That said, BA have at least got to try....so the only possible argument that they can 'reasonably' give to use the extra frequencies is the basis that they are trying to serve a different market from the LHR-DME route.
From what Virgin have said, it is difficult to tell if they are going after one or both daily London-Moscow frequencies. I may be wrong, but it sort of sounds like just one.
The rather more interesting question is who will get the other one. Sure, easyJet seems quite obvious but they are going to have to go some fair distance to prove to the authorities that they can do what is necessary to allow codesharing on their flights (as required under the bilateral by the Russians)....plus there is the question of a certain history of them taking the London-Cairo route to scarce capacity hearing (this was some while before the Egyptian troubles), winning the frequencies but never taking up the route. Sure, Moscow is a totally different market, but I am not sure how the UK side view carriers 'playing the system' but not following through with what they've promised..