"I think the best explanation of the "whole nine yards" is that certain sailing ships had 3 main sails and each of them used 3 yards of fabric."
I think a mainsail had a lot more than 9ft of fabric
. You're thinking of the phrase "3 sheets to the wind" --a hilariously apt metric for drunkenness in terms of how much leaning is going on (putting additional sails against the wind would lean the ship further and further over until it 'keeled-over' --at three sheets, or 'full sail'
)
TCB