Howabout The backstop IS a genuine problem and the EU bent over backwards trying to help the RoI there.
In fact, the UK has tried to use NI to leverage its cake options without the 4 freedoms;
the WA does succeeed in this to a small extent - hence some members claiming Barnier gave away too much.
The only border solutions are:
a) Technical magic which hasn't been invented
b) A trade deal with frictionless borders
c) NI to bugger off to the Republic or elsewhere out of the UK
The ERG brought in some customs bod, who just spoke to the HoC on his subject, NOT on the phyto-sanitary checks etc which are the main problem for the RoI
However, the main problem is the UK wants to leave - but keep all the bits it likes,
e.g. frictionless trade for JIT, faming & agriculture, also passporting, flights, Galileo, electricity connectors ....
Barnier showed his menu of options, with the choice of option depending on UK red lines
The only option that satisfies all UK red lines is Canada+,
in which case we need NI to bugger off, or maybe have joint rule with the RoI
However, the govt hated Canada+ anyway, because of all the trade benefits we would lose