Sumiotoshi is one of the first techniques we teach to the kids. Last night we did a couple of really fun variations on sumiotoshi, one ending in kategatami. It was awesome.
Katagatame as in the choke?
Out of curiosity, can you provide a Youtube link to your version of sumiotoshi?
Not sure how relevant, but how many people do a 'rokukyo' as a basic technique in their curriculum. I don't know that I've ever been to a dojo that does that, or at least they never did or talked about it while I was there. I believe the Birinkai might have that as a technique and it might be a lot like, what I'll generically call wakigatame.