the nastiest throws i have been subjected too were from Daito Ryu where both your hands are tied and you are dropped head first at the mat and scooped onto your back at the last minute.... Really these done properly are completely devastating killing moves/seriously mess you up moves n you have to trust your partner big time .... naaaaaaaasty! Also ones where you are dropped spine first onto a static platform like a knee .... again ... partner trust is a big thing here.
I am with you Iain on the acceleration in certain throwing methods being an indicator of usefulness in terms of damage or effectiveness. But like others have said, also some of the hardest throws to stop are those that manipulate the spine or neck with a twist force.... not sure you would describe those as 'throws' though ... more like knock downs or something.
I always say there are essentially three things to throwing.
Support - offbalance point - structure. any of these alone can take a person down ... when manipulation of these three things is combined to varying degrees they will definitely result in the person going down.
so in some respects speed or acceleration isnt an issue if we just want to take someone to the floor. If we want to cause some damage ... which of course we do
... then accelerating their mass into the ground or amplifying their masses effect by making them contact with a small surface area rather than their back is defo important.
Cracking vids by the way ... Fedors movement skill is far in advance of any of the others IMO.
Cheers
Chris