Jonathan

Dalen:

Koshinage, when it is done well, should feel to uke rather like he/she is tripping over nage. If nage is loading you onto his/her back and then dumping you off, they aren't doing koshinage properly. When nage is throwing like this, koshinage is always rougher on uke.

I would recommend turning your head toward nage and looking at him/her as you fall over his/her back. Do NOT look at the floor.

I would also second Russ's advice about grabbing hold of nage's shoulder or lapel as you take the fall and reaching for the mat with your free hand. I use the word "reaching" on purpose, mind you, as opposed to slapping. Feel for the mat after the manner of feeling for a wall in the dark instead of just blindly whipping your hand over and down toward the ground. Doing this, I find, lessens the impact of ukemi a fair bit.

Regards,

Jon.