Re: Aikido "Action Cut" Video with Matsuoka Sensei
They both seem to hold their body perpendicularly allowing their lower body to source power from the ground (not relying on friction but sourcing power as directly as possible up and down), hips (belly button) facing toward the delivery of force (Yoshinkan-like stance pretty much demands this), and with Shioda in particular (he's skinnier so it's easier to see) he seems to maintain a hsing-i like forward bow in his spine and across his shoulders. Shioda's weight drops appear to be both smaller and more focused (targeted).
Tohei is visibly relaxed. When I observe Shioda's atemi it is pretty clear that he is relaxed as well. One could profitably compare the old footage of Tomiki as well I think.