Make sure you never fly an aircraft after Chopjock has been in it.
Flying at max weight will cause brinelling in the rotor grip bearings, being overweight might just convince them to jam up completely. Engine and Xmsn chips will be more common, maybe not on Chopjock's flight (which is why he advocates it) but when some other poor bunny flies it later.
If you think the forces are the same whether overweight or not, try lifting an empty bucket with a rubber band, then fill it with water and try again. Goose.