Hi Drew, just got back to this post. Yep, I loved Ellis's seminar. I'd go again in a minute (sides, I'd get to see some folks again).
On Tenshinage...I recently kind of fell into a new (for me) version: top hand starts off palm out away from uke (but on the inside of the wrist), then as the bottom hand unballances uke, you cut with the tegatana to uke's neck/collar bone. Done well, it produces some **really** nice flying ukemi
With good forward focus and a little momentum, uke's feet go all the way over the top, their body basically rotating around the bottom hand. A nice variation after the initial xstep...
xstep in once, lower hand unbalances, xstep in again cut, xstep back as you complete the cut. Be carefull of uke...if you drop them out of their fall too quick, they land on their head.