Are we suggesting that the TPE and Northern franchises have been let on the basis of longer trains and more services to the airport, but there isn’t actually enough capacity at the airport?
Assuming the Castlefield corridor was sorted out we’d have a Northern Calder Valley service that presumably could be up to 4 cars heading for the airport as well?
That seems to be the whole basis of franchises, someone comes up with a fool of an idea of a service level, it gets written into the franchise requirement, then the poor buggers at the bottom end of planning have to work out how to make it sort of work, while all along someone at the top end of planning knew it wouldn't, while also knowing they could be elsewhere before the proverbial hit the fan so they didn't have to tell someone even higher some unwelcome answers to questions over whether it would work or not.
What is it, nine years since the ECML timetable that had to have extra services fitted in between existing ones without altering them, when it was blatantly clear to anyone with a passing knowledge that it would always require a full rewrite otherwise it would be unworkable? TPE-North was just one stage further by implementing an unworkable timetable before it was rewritten, possibly because too many of the old hands, unafraid to speak up, had been lost in the MK move. It's not the only route that's suffered from it GTR routes certainly have, but it's the most obvious when things go wrong wrong.
In fairness the Dec 2018 timetable had short turnarounds that limited any problems with platform capacity: not least because so many trains were failing to reach their destination due to inability to keep to time.
Go back even further and the problems were obvious with VXC's Operation Princess in 2002: more services with shorter sets often on congested routes with lots of conflicting moves, within a year many areas had been totally cut to improve performance: something neither practical or acceptable on TPE-North's routes (as played out when Scarborough was effectively becoming cut off from Malton), which I suspect would also have been the case with VXC had it happened a few years later. At least then it could be blamed on VXC being wildly optimistic in what they wanted.