Tony,
I understand you're point and you're definitely right, it is a risk. I knew that so I put my all into proving I wasn't. (Of course, that doesn't mean I didn't make mistakes.) Also, I should have mentioned that the shoots I have worked on have been low/no budget primarily, never major motion pictures.
Because they were low budget productions, I was working on a small crew where sometimes I was doing several jobs so I've learned about how to be a 1st, a loader, a DIT, a PA. I have gained some useful experience in the last year and a half thanks to those projects and at this point I feel like I would be taking a step backwards. By no means do I think that I am above doing any of those jobs, however. I would still apply for and work just as hard on a set in any of those positions but all of my experience has been as a 1st AC (and sometimes filling other jobs as well,) so I think it's acceptable to aim for that position on some shoots.