Thanks Monty!
It is just that I was struck by the notion of Waterloo International's platforms being brought back into play, and that Caledonian sleepers could be run to and from Waterloo with 92s.
If - and I appreciate that this is a non-trivial if - the existing timings and service robustness could be maintained with Waterloo - Kensington Olympia - Willesden Junction - WCML routing, it could be well worth considering as Waterloo is more central than Euston, has a direct link to Canary Wharf. It would also release capacity at Euston if it could be fitted into the LO procession towards Clapham Junction.
Perhaps as importantly, it is just across the river from the MPs who've kept the service alive in the first place..... I well remember how comparatively convenient it was for the civil service to go directly to Waterloo for Brussels and how comparatively inconvenient it became to go to St Pancras!
Tobbes