How about posture? I work with Loreto Garza. He has kind of a permanent shrug I guess you could say. Almost like he's constantly protecting his chin, even when he's relaxed. After some time training in MMA is there any traits you notice among those who have trained the longest?
I would think most systems would have some trait that gets trained in. I train in Aikido. My partner says I glide when I walk. Almost like even though I'm moving I look like I'm standing still. When we walk the yard, he has a difficult time keeping pace with me despite him being at least six inches taller than me. I attribute this to me, paying special attention to my foot work, cause I wanted to be able to use Aikdo foot work to gain advantage and position for utilizing Kajukembo techniques. What I would do, is practice moving like we do in Aikido while moving around in everyday life. As a result I can cover a lot of space quickly and effortlessly without thinking of my foot work.
So even something as simple as someone who never stands with his feet parallel to each other, or is constantly changing his position as others around him move about, may be signs. These things get trained in, and probably most don't even notice.