I think Tamura Sensei's irimi is amazing. His timing and sensitivity is excellent. He cuts straight up uke's center line and uses elbow power (as opposed to shoulder power) to destabilise Uke. I find it interesting that he has virtually discarded tenkan. Sunadomari sensei did the same thing when he got older.
he might have abandoned tenkan because he had experienced this as a real weakness of modern aikido.
Tenkan creates wonderful aesthetic. Irimi, omote and ura have stood the test of time. A warrior probably would rarely ever have done tenkan in a real encounter.