Thanks, Joe, but I still don't see the technique I am used to, though, of course, I'll take your expertise as a given.
The kataguruma I am used to involves taking uke from behind, grasping his collar, bending nages knees, then coming up (sometimes with an assist to uke with the other, free hand) and rolling uke over nage's shoulders. I hope this explanation makes sense? When it was done to me, I rolled over nage's shoulders and landed, light as a feather, on my feet. A truly joyful experience - not a slam in sight.
Without seeing the mover you are describiong I cannot ascertain exactly what it is,If you as Tori are goingg behind uke, grasping his/her collar from the rear , loweriong you postuure and bringing uke over the top of you shoulders,this appears to be a movement described in one of Saito
Sensei 5 vol. set of books.Cannot recall vol/pafe no, but I think it is a variation of irimi nage.If i get a chance[very busy right now]-getting ready for attendance at a course our area, I will check it iut.
If you want to see Kata Guruma, try and locate Wolfgang Hoffmann[ Senseia German judoka] on You Tube].I believe he was pretty good at this waza.Oldfootage of Hoffman Sensei may be available. Cheers, Joe