I think that I apply the entity theory to some of my physical skills because I see the physical body as less malleable that the brain. For example, I've never believed I had unlimited potential when it learning gymnastics. I don't carry the same type of body as those that typically excel at the sport. I do believe I could learn some skills but I don't think I don't think the potential for advancement is that high.
I apply the incremental theory most other things in my life - growth in my mental, emotional, spiritual, social skills. My ability to learn, parent, play the guitar, practice and teach yoga. It seems that our GAs our based on this theory, that we can always better ourselves and aren't stuck it our habits or ways of thinking.
I think that my occupational choices have been influenced by theories I have about myself. For example, I used to run a ton and I carried and entity theory that I "was a runner." I was "built like a runner" and therefore was pre-destined to be a runner. It was a natural skill for me, I experienced few setbacks, and it became easier with more practice. Eventually, however, I reached a peak and felt I couldn't get much better than that. I think this is common for a lot of athletes. The gains you make in your skill become smaller with more practice as you reach the limits of your biology/mindset. At that point, I ran to maintain the skill but didn't continue to challenge myself and eventually I lost my drive to continue it. I can't blame it on lack of dedication or practice - I was a college athlete and ran everyday. Even as a mediocre college athlete I was still a much better runner than most of the rest of the world and found safety in that knowledge. I never had a major "test" to my identity as a good runner. But once I completed my college career, I dropped the occupation fairly quickly. I could see myself pick up running again one day because I recall fondly the flow state I achieved when I was really fast and competent at the skill. Right now, the challenge is too high though and my skills are way too low that it would take months of practice to get back to the flow state. Interestingly, even though I haven't run in years, I still identify as a runner or with other runners.
I have evolved into a more incremental self-theory, especially about everything beyond my physical skills. I see the ability to parent better, increase patience, become a better person, and increase my compassion and in that aspect all of my social occupations feel like they will only get better with time.
I do believe I hold the capacity to become a guitar virtuoso... or at least really competent, even though I don't come from a "musical family." I was going to use the excuse that maybe my hands/fingers aren't big enough to a great player but a quick google search proved me wrong - there are a few famous guitar players with small hands. So really, in my mind, there isn't anything holding me back except my dedication and resources to learning the new skill. And resources beyond time aren't even an issue because most of the best guitar players were self-taught The Secrets of Self-taugh, High Performing Musicians. As an incrementalist, I believe that any set backs I'll experience are only due to a lack of dedication or time spent practicing. I understand, however, that entity theorists may struggle with this more as they may see a set back as a sign that they aren't meant to play the guitar or don't hold the inherent skills to do so.