hm.. i always thought during training, the weight we carry is
heavier than the actual load, cos we carry dummy ammo which is
heavier than live ones. yes, its true i never weighed the load i
(or any of my peers or men, etc) carried. perhaps its my own
perception - because of my weight, i didnt think a normal
infantryman would carry so much. of course we might be mistaken, or
it might simply be that, we can actually carry load heavier than
our own weights!
anyway, from what you mentioned above, FBO can easily be 90kg.
however here you said it goes to 70 kg max for gdsman.