What do you define or understand "kata"?
How can aikido be learned without using kata?
I suppose in this instance I am referring to a more strictly formal series of movements and sensations.
I would not call ikkyo or shihonage kata - they are waza. In my experience Aikido trains waza in a more fluid and dynamic context than Daito ryu during regular training.
And at the end of the day Daito ryu actually calls them kata too.
Isn't this the aim of every "good" technique? (That it is tori who decides what happens. Not uke.)
Exactly - which is why I don't find it to be much of a revelation from Gaurin Sensei that studying Daito ryu can help you understand Ueshiba's Aikido, because in Daito ryu techniques are done so that "no ukemi can be taken."