Re: Two Swords in Aikido
I used to have a copy of Hiden from 1992 or 1993, back when it was a quarterly magazine, and there was an ad calling for uchideshi to Saigo-Ha Daito Ryu. Included in the syllabus it claimed to teach was Saigo-Ha Daito Ryu Nito.
Usual caveats apply, but here is one example of nito in a (purportedly) Daito Ryu organization.
With regards to the video by the OP, that looks to be an extension of yokomen uchi - tori's atemi should continue down to uke's wrist in a taijutsu form, and the use of two bokuto emphasizes this. I would consider the content of the video a valid training exercise.