I'm not sure you're understanding the point. In a non-election period, there's a good incentive for both parties to seek a win-win outcome as that's the rational outcome. In an election period, Trump doesn't give two hoots about Britain. Think of the tariffs on China as an example. Everyone knows they hurt America, but he did them because they boosted his base. His base isn't going to care about giving Britain a good deal, and nothing in Trump's history suggests that's likely. He sees trade in zero sum terms, and in an election period, that's even more so.
I'm suggesting that because Germany and the US are in election periods, they are more likely to play hard ball, which given the timescales the government have forced upon us, means it's more likely we end with a poor deal, or no deal at all. We've seen this in Britain with the Tories setting stupid timetables on the negotiations, purely because they were in an election and wanted to appear tough.
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