I don't think "knowing how to play" has any part here, certainly not for me. Not in the content that has an automated queue system. On a newly dinged character, I can be aware that my performance is horrible, but that won't stop me from doing any content for which I'm "eligible".
Now in any content with human interaction -- I will go on a guilt trip if I think I'm not pulling my weight (even in a 30-man normal-mode pug of an old raid tier, where one can feel "invisible", if you wish).