I don't know for sure, Liv, but if the EU are talking about making special exemptions for NI I presume this is the type of thing they would be considering. It's been shot down by May though.
We are really talking in a vacuum here; in the absence of any suggestion at all by the British government of what they want to do, and the immediate refusal to consider anything anyone else suggestions, it's all a bit up in the air [understatement]
Ifailed, there is absolutely no comparison between the effects of the violence on the people of NI and the rest of the UK. Obviously the deaths in Ireland and on the mainland were appalling, as is/was the after effects of smuggling, gangs, etc. But the violence in the North affected every single second of every single day for years. There isn't a person living there, I bet, who doesn't have personal experience of violence, who doesn't know at least one person who died or was serious injured.
It's relatively easy for those living on the mainland to not worry too much about violence in NI. Hence their ability to dismiss worries over border issues, and just tell themselves it's "an Irish problem".
Maybe I should have said "in comparison to the risk in NI itself, the rest of the UK is at very little risk of violence" - but I thought that point was obvious 