Yes, the only issue is that if it sends you that way and then your train is cancelled or heavily delayed, then you are stuck there for quite a while with nowhere really to sit with a lot of luggage and if there is trouble down south, Avanti can and often WILL cape the Picc services so there are enough seats for the more important WCML trains to Glasgow. Going via Crewe gives you the services from Glasgow, Edinburgh, Blackpool North, Liverpool, Chester and Manchester as well as the London North Western from Crewe to Euston to play with if that happens. And, depending when you travel, there is also the Holyhead return in play as well so eight services really if all goes well.

I've just, while typing the reply and seeing your edit, got my ticketing guide out and if your ticket shows ANY ROUTE PERMITTED or AVANTI AND CONNECTIONS ONLY then you are covered for this going that way.

Edit: You could also, in theory, take the Transpennine Express service to Sheffield or Doncaster and return via the Midland and East Coast, though the ECML does normally tend to be when Ticket Acceptance is on unless the fare permits the valid routing