Just to be clear, the longer CGH runway seems a little longer than ABZ (?) We (BA) operate MLW 64.5T (I think?) A320s in there routinely with no special restrictions / rules, although naturally one takes more care / planning / briefing. In fact, I believe we have even tankered in there on occasion to MLW. We now have a F3 SOP for the 320/1 to save 2ps worth of fuel, but I doubt many would follow it at ABZ
I have done a tough and go there due combination of gusty wind, managed speed + ATHR and incompetance
An A320 with 176 people on it by definition will be not far off MLW, unless they are all children without baggage...
The pure runway length I would therefore think not the major issue. The state of the runway surface is, of course, a different matter completely, and I find the A320 series quite easy to skid/slide on a slippery surface - i.e. antiskid hammering away and little retardation.