The first step would be meeting him in person.
I just flipped through my masterclass book Uchimata by Hitoshi Sugai, and all if the versions in the book are classified by the type of grip that is taken. There is no mention of co or o or straight up the middle. It is only Ai-yotso (same grip) or Kenka-yotsu (left vs right) and the style. Ie Ken Ken, Russian belt grab, or pushing style. I does not classify the version by the position of the leg. That being said, my sensei has always differentiated between co, o or ken ken, So I am well aware of the terminology.
O Uchi (planted thigh)
Ko Uchi (lifted thigh)
Taka Uchi (split the middle)
Discuss.
*edit: had the first two bass-ackwards. thanks drew.
I use the O-Uchi-Gari to bait him in stepping away from it, from there my UchiMata rate is the highest. It's also my favorite throw!
O-Uchi to Uchi Mata on the step out 45
Ouchi Gari is an awesome set-up for my two favorite throws - Osoto Gari and Uchi Mata. Watch Yamashita Yasuhiro - his Judo career was basically a masterclass in Osoto Gari/Uchi Mata set up with Ouchi Gari.
Yeah, like I said I spent years trying to do beautiful, hippy Inoue style uchi matas but the only ones that ever really worked for me were ouchi -> ken ken style.
I think most Uchi Mata, even Inoue Kosei's (especially when he was fighting in the +100kg category), are finished with some degree of ken ken. If it's good enough for Yamashita Yasuhiro it's good enough for anyone.
Besides, aren't you something like 195cm tall? So your Uchi Mata is going to be more leg than hip on 99% of people for purely physiological reasons.
I'm an American, so I'm 6'2"that's 188 cm, or 4.11 cubits if you want to get biblical. And while I know that given my height in my weight class (plus the fact that I have longer legs for my height) that my uchi matas are going to be more hopping, but I never got past wanting to do this: