Only for Scots or for EU citizens - English people have to pay(due to the fact that Scots willing to study in England have to pay for their universities, to it's reciprocal).
(I'm not 100% sure how this is enforced. It rather seems as though getting a cheap flat north of the border and declaring that as your normal residence for the duration of studies could be worthwhile if you can afford it...)
It's debatable whether it's very ethical to do what you suggested - though I don't imagine it's particularly common.
The university would presumably also expect a Scotland-resident student to take Scottish exams at a Scottish school, which is a separate system to England, so even more hassle.