Honestly, I wish more people did this. Most of the time I get a DF group, and nobody else will bother saying anything, new or not. They just run off towards mobs as soon as everyone is in and start pulling. I end up having to explain boss mechanics on nearly every run, two thirds the time I'm marking for our tank because he doesn't know how or doesn't realize its importance (and I'm a BLM).
The worst is when you get some arrogant, impatient tank who cant wait patiently til you finish explaining the fight and runs in unprepared, and gets everyone killed.