What is purpose of fullers on blades?

[David]

Originally Posted by motan

Just few additional remarks:
I, and others, have mentioned strength/weight ratio as a factor. But this apparently very logical argument has a big hole in it. The main strength parameter to increase (per weight unit) is the lateral stiffness and this is NOT a good idea because it reduces lateral flexibility and increase the chances of bending and breaking. A lot has been done in sword forging to achieve the exact opposite-more flexibility, like in katanas (very functional swords indeed).
Air-pocketing and blood grooves do not make sense either if we consider physics and physiology. Suction (underpressure) does, in theory, because in battle situaton, a sword would have to be inserted and pulled out very quickly (much too fast for bleeding to develop). I beleive in empirical solutions, so this will remain a feeble theory untill experiments are conducted.
Why fullers then?

Forgive me Motan, but it does seem to me that this question has indeed been adequately answered. The blood letting "answer" has been known to be a myth for many years know so i don't think any kind of experiments are necessary to prove this point.