First, right off the bat can we all (myself included) collectively move away from military metaphors for trade negotiations?
I realize "war-gaming" sounds a lot more elite and tactical than "drunkenly fantasize" but it's honestly so unhelpful.
The vision is a scenario whereby the EU is pushing the UK hard on fish because the French want it, and Poland tells the French to back off and shut up to get a deal done.
a) Poland needs to prioritize getting a deal over relations with France (lol);
b) France must acquiesce to Polish pressure (rofl);
c) The French Parliament must subsequently ratify a deal in which one of its key asks isn't included (bahaha).
Yay?
I'm not sure how you get that impression from the events of late 2019. Nice internal customs border, btw.