Re: Red tape
I'm glad I'm not the one sorting out the mess the UK mainland company I'm working for has. They sell stuff to a company in Northern Ireland which sells into Ireland, who sldo buy stuff from Ireland which they then sell to us, and other EU member states, as do we.
So what was a simple and straight forward arrangement is going to get incredibly complicated to the detriment of everyone, but particularly that Northern Ireland company.
And, even when trading directly with the Irish company, it's not certain that goods traded with the Northern Ireland company won't be considered 'at risk of entering the EU' and have duty applied accordingly which has to then be reclaimed.
The TL;DR synopsis on their last impact assessment was a simple but accurate; "fuck knows".