SmilingNage, thank you for bringing this again
to us. Actually the one being impolite was her. Here, read:
And you might be a fat woman in a tutu. I've never seen you either.
I'm certain I haven't stated how I do koshi nage.
1. to keep uke from landing on your leg
2. to teach nage to bend his knees to scoop up uke with his butt, keeping uke on the small flat of his back
3. to keep koshi nage movement from being more of tripping motion like in judo. Not that there is anything wrong about tripping; we talking aikido throws.
1. Uke will not land on your leg by doing a proper Aikido Koshi Nage a la O'Sensei, i.e. with "that" swinging motion.
2. One footed, cross-legged, heels together or shoulder width apart, if tori is smaller than uke, he (generic he) must bend the knees... but the goal is to keep your hip under uke's, not bending the knees per se.
3. It's not tripping but swinging uke over tori's hips. Nothing to do with Judo. Not that Judo's way is wrong, though.