I think that'd have been even more badly received by the majority of the public - and the ever-present media! At least running as far as Peterborough (perhaps a limited service to minimise the reliance on London crews) would allow them to take their chance on a suburban train onwards. Perhaps things would have been easoer at Finsbury Park with a slightly more frequent service of suburban-layout EMUs. What was the situation with access to Hornsey depot though - was it actually blocked by a possession, and was this planned?
I agree it probably would have been badly received, but tough, at least it wouldn't have caused the Finsbury Park chaos, and regular users of Finsbury Park wouldn't have turned up to find the station in meltdown due to East Coast passengers blocking up the station with their cases and inability to work out what to do turning up at an unfamiliar location.
I definitely think it would have helped if EMUs had been arriving rather than East Coast trains, apart from anything else this would allowed reversing via Canonbury, which I believe isn't an option for East Coast. The only issue is that Canonbury is essentially a single-track reversing location, and unless each train was double-ended then the reversing capability would be fairly low. In the circumstances I suppose there wouldn't have been the time to arrange 12-car EMUs in an emergency timetable. But, in that case, since the railway couldn't provide a workable East Coast service to London, the service should have been totally suspended.
From what I gather there was a planned block at Hornsey, no idea if this also overran. I don't think this should have caused that much shortage of stock on the GN side though, as most of the outer suburban stock tends to stable at the country ends overnight (Letchworth, Peterborough, Cambridge and Kings Lynn), with Hornsey tending to be filled with class 313s. I've no idea if this held true over Christmas however, so perhaps this was an issue.
