Blockades and AI timidity

[Grognot]

AI behavioral issue -- AI appears to never attempt to overpower blockades, even when the outcome isn't really in doubt.

Ex. -- in an MP game, the UK player has for multiple months successfully blockaded the entire Spanish fleet excluding transports (total 35h / 22l -- in other words, full initial strength) with... the Portugese fleet (8h, 8l). The Spanish transports are unprotected in a separate zone, ready to be captured by an opportunist.

Max. Spanish casualties, one battle ~ 25% x 16 = 4 (all light). Even assuming this worst case (p=1/6), requiring 5+ casualties to be caused with 35h / 18l = 53s(remaining)... Spanish victory is 100% likely, because the +1 die roll bonus (1.5x heavy ships) = min die roll 2 = min 10% cas inflicted = min 5 kills.

That's in the worst case. Expected losses more like 0.15x16 = 2 light ships, for +2 PP, and expected Portugese casualties ca. 9 (+1 die roll bonus ~ average roll 4.5 or so, ~17.5% rate, probably ~54 Spanish ships after losses).

Granted, Spain might be waiting until Lisbon falls and the Portugese fleet vaporizes, for free (instead of 2 light ships), but Spain is also nominally at war with Turkey, for which these fleets might be useful... and it'd be dangerous to stay there if another naval power might be considering DoW'ing Spain and augmenting the blockade to the point where successful flight is far from automatic. I've also seen AI timidity regarding blockades even in major-vs-major situations where Instant Fleet Vaporization isn't really an option.