There are mechanics in dungeons but none that require lengthy videos or walkthroughs... most bosses usually can be explained in a sentence or two.
Personally I go into dungeons blind, and if there's something in the end I still don't understand I'll look it up. (And yes, that's coming as DPS, so sitting through those queues is my specialty).

Must say I don't have the guts to go in as healer first, for anything.