Here is a little bit to add to the stew.
How are you doing tenkan undo?
I learned originally from David Rodriguez sensei who was previously with Toyoda out of chicago, and also I am surrounded by Suganuma style aikikai in Oita prefecture.
The tenkan undo that I brought with me from america is a ki no nagare, flowing style. I can't say if that is exactly what Toyoda did because I do not know, but that is what I learned. It focuses on ki, breathing, and leading. The aikikai that I am doing right now starts from a firm static position. You BEGIN by entering, by pointing at their belly button. This produces a response, the desire not be pointed at, essentially you invite a push from them. Then without changing the position of that fight, you bring center to it, and then line up outside of it, eventually sinking down after dominating your uke's position.
I am sorry for the lengthy description of all of this, but it just shows the diversity in the aikido community when it comes to these dynamics. The Suganuma shihan version is almost like an irimi technique, it certainly feels fairly omote. The Rodriguez sensei version emphasizes looking past that and moving behind, a very ura ending. Which is better? I teach both to my students now. Confusing but in the end worth it.
What do you do?
Does anybody practice irimi body movement every class?