I think I would almost certainly say yes but would prefer to bow to the experience of any experienced engineer.
I believe that the limiting factor in the older baldes was the integrity of the blade root structure.
You may find in these threads history of an Isreali machine that a blade parted company from, AUW rumoured to be quite excessive, and another NZ machine which a blade parted company from, rumoured to be within AUW but it was a spraying machine in a cool climate, more power y'know.
I know of one or two machines that flew abour 22-28% over AUW for a while but the blades haven't failed - yet - but then again I never saw the spindles or history of possible changes.
A massive no no I would suggest, they just dont fly well, a bit like the overloaded Aztec or big Cherokee, they tend to wallow fore and aft. Not at all pleasant
tet