The club's owner Charles Green said this week that the Ibrox side would have no option but to quit Scottish football if the planned 12-12-18 restructure goes through against their wishes, but McCoist feels that after the battle to retain the club's 140 years of history north of the border, it is something they would have to think long and hard about giving up, not least because of a potential knock-on effect to the Scottish national team.
"If it [working their way up through the English system] benefited the football club then it's something you'd have to consider," he said. "But there would be other factors as well: if you did that, would you still be able to leave a team up here which could play in the SFL or whatever it may be?
"Contrary to what a lot of people might think, Scottish football is very important to us all and to me, so the conscience thing would play a part. Supporters of other clubs would think it was great for the Scottish game if Rangers and Celtic left – and that might be the case.
"But we've been part of Scottish football for 140 years so it's not a relationship you would want to end without giving it some serious thought. And as British as I am, there was nobody who loved playing for Scotland more than me, I loved the opportunity to represent my country."
In the week Celtic chief executive Peter Lawwell unveiled a solo shirt sponsorship deal with Magners, McCoist said that any exodus southward would have to involve both Glasgow clubs.
He also said that if Rangers are expected to buy into this new set-up, it seems unfair that they would still be bound by a transfer embargo imposed upon them under the existing league set-up.
"Peter's made it clear that he thinks they can handle almost anything without Rangers, which is his opinion and that's fine," McCoist said. "But I'm of the opinion that if it were to happen it would certainly have to involve both clubs."
Sebastien Faure, the Rangers' French full-back, is another who fails to see the sense in the restructuring plan mooted this week and feels the club is right to explore other avenues.
"It is complicated but why not, if there is a chance to play against teams in England?" Faure said. "It is not logical to win a division and then have to play against all the same teams again. It would be far better if you could progress – third division, then second division, then first division – through the leagues here."