[vidarh]

As far as I understand, there's only been a couple of elections where losing the Labour majority in Scotland would have made a difference for Labour.

It's true that a Labour government would likely have a far smaller majority without the Scottish MPs, but when Labour has won, it has usually been with far greater majorities than that.

[blueskin_]

It would have in the most recent general election, while the general consensus is that hung parliaments[1] are only going to become more common if not the norm in future.

[1]That is, no clear majority, requiring a coalition government