I recently traveled on American Airlines and I discovered something interesting.
I live in Seattle, and as a result, I have a Frequent Flyer card for Alaska Airlines.  Alaska and American have a new partnership.
As a result of this partnership, having an Alaska Airlines MVP number, grants you early boarding on American Airlines.  I have the base status on Alaska, but, I was still able to board the plane before about half of the rest of the plane.  American boarded their higher tier frequent flyer, high tier people in the OneWorld frequent flyer plans, and First/Business class before me, but I boarded before the people who purchased regular tickets, with the AAdvantage ‘Gold’ status members or OneWorld ‘Ruby’ status members.  See here – https://www.aa.com/i18n/travel-info/boarding-process.jsp
So, if you are traveling in coach, do not otherwise have any airline status, do not intend to build miles on American or OneWorld airlines, and are not flying in business/first, you can sign up for the Alaska MVP program and board before most people.  It doesn’t cost anything, and it does not even require you to have ever flown on Alaska Airlines.
Enjoy!
-Brad