It's not a theory to me; just what I have seen and touched. I've seen tekin prez's and ty's cars with the castle esc and motor in them. I was told it was the Tekin system prototype. Same thing with the mini rage system.
Maybe things have changed since then, I don't know, but from that point forward I have not heard of a total rethink of the direction they were going at that time. So I'm fairly certain there is still a relationship between Castle and Tekin.
This is not to say it's a bad thing. I hope they put out a great system soon. I am not picky about the origins of a good thing. I'll buy it if it's price and performance work for me.