Seem that you are indeed right! Thanks for clearing that up!

To quote the relevant parts:

... It’s the fact that none of it is true. The overflow error never happened at all. It is true that Gandhi would—eventually—use nukes when India was at war, just like any civilization in the game, and at the time this did strike a lot of players as odd. [...] Since all leaders used the same basic diplomacy script [...] But at no point did a democratic score change, or any value approaching 255, come into it. That kind of bug comes from something called unsigned characters, which are [...] not something I used for the leader traits. Brian Reynolds wrote Civ II in C++, and he didn’t use them, either. [...] Gandhi’s military aggressiveness score remained at 1 throughout the game. [...]