I remember hearing all this in the early 90's when they actually had a firm and used to constantly tell us how much better their firm was than ours then
They probably had a point, but we'd always turn up for the derby games, I can't remember them ever coming down in numbers to Hillsborough Corner and doing anything, we were all there too in numbers, they knew where we were.
Apart from a few isolated incidents from small numbers, normally picking on your shirty fan or smaller numbers, (typical BBC Bully Boys) they never actually delivered in what they said. So I guarantee nothing will happen on Sunday, especially when it didn't in 92 or 94 when the off-field stuff was a lot more common.