Well, I'm usually not a big defender of CA, but I gotta be honest here, their defense is a good and logical one. That is, they have made the case that it's not a bug, but like ShellShock said, the problem is no longer a bug, but a bad decision-making process.

If it's true that if a player saves/loads each turn, the AI never expands, then there is something wrong with the deeper analysis the AI performs after loads. It's important to differentiate that, while this behavior by the AI may be dumb, it's not necessarily a bug. It may just be an overly-defensive tendency built into those more indepth reviews. If that's the case, it's likely the devs would not have seen this pattern during development for the bell curve reason CA mentioned. It may very well have taken the sheer number of games we've played to expose this tendency.

This may be another example of a negative consequence of too much complexity and/or too many variables. The more variables in an equation, the more difficult it is to ensure a favorable and outcome. RTW has a TON of variables the AI is supposed to take account of. This may just be an example of the cart getting ahead of the horse, of the complexity of an equation getting ahead of the AI's ability to make good decisions based on it.