Originally posted by DaveMcW
"Early Aggressive Defense"
I can think of 2 problems with this. Waiting for mathematics/catapults is NOT early. And waiting for the enemy to invade your land is NOT aggressive. Ditch the warriors and cataput and you'll have 1 Spearman = good Defense.
Well for most civs it is relatively early, particularily the French who start with alphabet and masonry, and can go for catapults as their first new tech. Bronzeworking can be traded for. Trading mathematics for yet another tech is then a good idea since the AI rarely builds catapults early in the game.
The reason for the two warriors is that it allows 1) flexibility in garrisoning cities, 2) sooner upgrading than archers.
Now it gets a bit complicated. The attack order against, say an enemy archer or chariot, is then A) bombardment, B) if succesful then attack with warrior. C) this either results in a win or a loss in which case there are three outcomes, one where the opposing unit is promoted and looses no hitpoints, one where the unit is not promoted and do not loose hitpoints, one where the unit loose hitpoints and is not promoted. In all cases but the first then use the spearman to attack.
Why not simply use archers? Simple, the archer, paradoxically, has too great a chance of winning luring possible promotions away from the spearman.
But why is it so important to let the spearman get the promotion? Simple, with catapults an elite spearman is capable of generating leaders on the offense. More importantly it also ensures a reasonable (and better than archers) chance of generating leaders on defence. This is even though defense only has a 1 in 32 (1 in 24 in some cases) of generating leaders.
It is also important to note that the "(relatively) Early Agressive Defense" takes place within your own borders, so make sure the road net is well developed. The higher the concentration of roads the higer the level of flexibility in shifting forces around and concentrate catapult bombardment on the enemy. Here the much lamented French show their usefulness once more, since they are industrial. The Greeks have the hoplite so this strategy is also viable for them too.