I think you've misremembered geography here - a straight line from "mainland" Russia to Kaliningrad cuts through Lithuania and Latvia, and to involve Poland here, you'd have to be drawing a line from Belarus. Additionally, when Kaliningrad was handed over to the Soviets, it was contiguous as part of the USSR. There was no "design" to make the Russians upset about it.

Map: https://imgur.com/a/xtBJAig

1992 Russia offered Kaliningrad to both Poland and Lithuania, but neither country was interested in a region with seriously underdeveloped economy and inhabited by Russians who wouldn’t feel either Polish or Lithuanian, nor would they speak the language.

> And if you look at the borders, it's pretty clear they were designed as a lock

Assuming you speak about Suwalki Corridor, those borders reflect pre-war borders of local counties. No mastermind planning to make it hard for Russia to make it from Belarus to Kaliningrad. In fact it was Russia who drove those lines in first place after WW2.

Only „problem” Russia would have to solve in eventual aggression is getting an army into Belarus. But they can just target the Baltics instead and strike from their own territory.

Impressive research! I have an story that is related to this kind of history research and genealogy but not with math. My great-great-grandfather was born in Gornostaypol [1], before the XX century. He came to Argentina with some of his children and my grandfather. Beyond my family and Internet genealogy will be very difficult to get information (without going to Ukraine...) and who can remember him or something about my family in 2023 in a village with minimum population? The Google search is more complex also because his surname was "men".

So... a post appeared in July 13, 2022 talking about my great-great-grandfather from the memories of a women who was born in 1938 [2]. Those are amazing things such as searching a needle in a haystack. Randomness helps.

[1] https://en.wikipedia.org/wiki/Hornostaipil

[2] https://jewua.org/gornostaypol/