as the title says, unlimited manpower is achievable through an exploit in multiplayer (unit trade option is exploitable)
there are two totally different ways of spawning manpower from nothing. They are not connected in any way, except that the result is the same. i write them both down here in one bug report, but in fact they are two separate bug (exploit).
1, ships. ships strength are not reduced when traded. trade any type of ship via diplomacy/unit trade option will cause receiving free manpower. the sender receives his manpower back to his pool, the receiver get them with full str. if he sends them back he receives the manpower also. this steps can be repeated indefinitely. the manpower gain available from this is limited because you can only open negotiation with an another country in every 8days or so (example: send 5battleship and receive 5battleship to/from your ally with a negotiation offer and both of you receive 10 free manpower. repeat it every 8 days. u gain 400+ manpower per year)
2, brigades. they are working very odd. they increase a unit manpower value, but not. the best definition i can give you: the brigade "manpower cost" is proportional to the unit it is attached to. so take an example. an infantry div costs 10manpower. attach an arty brigade to it for another 2 manpower. As long as your unit is on 100str, they "worth" 12manpower. so far so good. as your unit start to lose str the brigade manpower value is reduced also BUT no manpower is needed to "reinforce" it, because the brigade has no str value on itself. so if our inf/art is reduced to 1 str, only 10manpower is needed for full reinforcement. you may wonder how it is exploitable. via diplomacy/trade units. if you sell your inf/art you will receive 12manpower back to your pool, however if you receive the very same inf/art you will only need 10manpower to reinforce it from 1 to 100. so 2 manpower was appeared from nothing. to use this exploit to the maximum the best is mil/ac (because it's very cheap to repair). send 5mil/ac to your ally, and receive another 5mil/ac and both of you receive 10bonus manpower. (at least this exploit is not for free, because repairing them costs a lot of ic compared to ship explo)
