You see that particular stance fall away when one is doing something other than kihon, and especially when facing multiple attackers. I will say many guys likely finish their zanshin in that stance so it probably seems like they are always in it. I love it for pins and finishes as well. Most guys will start and finish in a basic kamae, regardless if what they are doing.
Mr. Payet is a good example of one not always sticking to basic kamae.
Also, a yoshikan honbu offshoot has a different kamae and zanshin (slightly) but I can't recall who.
I have only really experienced Yoshinkan twice - once a dojo visit in Toronto and the other was sort of an Aikido fest at my dojo in Himeji where I invited an Aikikai Shihan and an instructor from the Senshusei course down and we all spent the time cross-flavoring. Stance variation was interesting then and it still holds a fascination. For me one of the most difficult things about dojo visits is adopting their stance - its amazing how that can interfere was harmonious training.
Final point - is I never felt that the Yoshinkan people I trained with were locked into their stance and were never as robotic as legend would have it. Good strong aikido.