1. I have "spoken" with "Harkonnen" somewhat about the T-80UD over the past 2-3 years. There has been NO confirmation or hint that the SKIF style engine deck was more than a prototype.
2. For T-80 developement, there is a LOT of stuff that went on. George probably has the best synopsis on the turret development. I would say that with Kharkov working on their designs and Leningrad working on not only their designs but also the 10 pre-production production tool-up tanks, that there is some strange stuff out there, real one-of-a-kind. Add into this that Marshall Ustinov was trying HARD to streamline tank production and design, and you will get even more variety.
Remember, the T-80 was a development to try to "fix" some of the problems of the T-64 while adding in the gas turbine engine, all without stepping on too many design bereau's toes or manufacturing plants bottom lines. What a wonderfull mess! Really. Since these one-off tanks still exist, they give a good insight into Soviet tank manufacture and design thinking at the time. But, of course, it adds another layer of problem for us modellers to figure out!
As for "not being Jacques", hey, I love the compliment it implies, but really, anyone can do what I am doing. I do not have any special contacts or special insights...I cannot even read Russian. I just do a lot of research and pay attention. So no fear of insulting me.
I would be happy to see 100 T-80 tank researchers with me.
And I am excited to see what Guanghui's build finally looks like. He is doing a very good job and inspiring some excellent discussion.