Rhyme & Reason? Some, but there's still work to be done.
Poland wins my prize for most ridiculous diplomacy AI with this stunning move:
They sent a diplomat to offer trade rights and alliance (to me, the HRE), which I accept, and on the very same turn attacking a fully garrisoned Prague with a family member and two depleted units of peasants!
That's neither diplomacy nor warfare, that's just pissing away your credibility and reputation.
So I crushed them, naturally, taking all their baltic provinces and their capital and only stopping because the russians started looking scared and you don't mess with a scared russian. The silly poles agree to a ceasefire, called by me this time, and on the next turn they blockade my newly acquired port in Riga with their "navy" (two leaking boats with skeleton crews) that I didn't even know they had. My field army is only two squares away from their new and largely unprotected capital!
I guess being known as "weak" and "untrustworthy" wasn't enough. Once I get home tonight, they'll be known as "dead"!

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