[Stooky Bill]

Thames' Citytv proposal on Channel 5, as reported on BBC News:
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Always interested to see how this would turn out - although it'd probably collapse in 5 years

It could have worked, they'd probably not have come on air for a year or two and the economy had improved by then. As was seen by the number of bidders a couple of years later. 

IIRC the plan was for several city based stations rather than a national service, so more costly but that would have had some advantages. It could have been rolled out in London first and then to other cities. The transmitter network wouldn't only have been smaller but also rolled out gradually, and the retune scheme more manageable.

Thames had a lot of experience and facilities of course but one issue was that the decision was only made in mid December 1992 so a lot of their staff were gone by then. That said a lot of the people working on Channel 5 when it did launch in 1997 were Thames staff, then working for their then owners Pearson.