On stability in Bts, playing a game as Greece right now where I have 3 stars in everything yet am "Shaky." I've read the wiki more than once and many articles on stability and I still don't completely get it. I love the concept of it but it is truly difficult to master.
It's been complained about before that the stars (especially the "3 stars" rating) don't tell you as much as you need to know. IIRC, 3 stars basically means "Shaky-Stable," so if the numerical values are low enough--if you're actually flirting with 2 stars in each or even just most of the categories--you could have three stars across the board and still be shaky. I think I've had games where I was rated "Unstable" when I had 2 stars in one category and 3 stars in the rest.