[SGTGunn]

Well I'm not sure if it's part of the AI routine, but I know that I could not resist such a juicy target as a tank with infantry riding on top. Infantry riding exposed on the outside of an armored vehicle are HORRIBLY exposed to small arms and HE fires. Infantry's only protection against fires (when not dug in or behind hard cover) is dispersion and concealment. Piling a squad onto the top of tank pretty much eliminates both. It's almost too easy to machine gun a rifle squad that is all huddled together on top of a big, obvious steel target. Plus all of the MG rounds (and/or artillery or mortar fragments) ricocheting off the tank itself just provide additional opportunities to lodge themselves in the hapless riders. Historically tank riders in WW2 took horrendous casualties if they were caught mounted by the enemy. Veteran infantry quickly learn the double edged sword of working with armor - it can be nice to have a big fat tank to hide behind, and to have available to blast bunkers, pillboxes or other hard targets, but on the other hand AFVs are the ultimate bullet magnets, and the environment around them can turn unsurvivable to a grunt very, very fast. Plus when they button up, AFVs can very easily end up running over the troops they are working with (though luckily that's not simulated in the game!!)

Adrian