Dubby said:
An exoskeleton doesn't add to the wearer's strength, it -replaces- the wearer's strength. This is because the exoskeleton is many MANY times stronger than the person is, and therefore any strength applied by the person is neglible compared to the exoskeleton's. This also means an elderly man with bad hips using an exoskeleton can apply just as much force to an object as a heavy-weight boxer using an exoskeleton.
When speaking of an exoskeleton that increases the user's strength many times over, that explanation makes sense, but when speaking of power armor, I don't believe that it does. Power armor is
not many times stronger than the person is, and by your own design implementation, some characters will gain nothing from power armor, and in fact may be able to exert more force than the exoskeleton itself, at least from a load bearing perspective.
Seems to me that the only way that design makes sense is to claim that the suit of armor weighs an extremely large amount, and can only support a couple hundred more pounds on top of its already heavy weight (2000 lbs or some such?), such that the strength of the human wouldn't even be a factor. Of course, if its done that way, some characters should actually lose strength.
Personally, I would argue that a society advanced enough to create a powered exoskeleton would be smart enough to use carbon fiber or some other light weight material to do so.