Trying to use our whole kit is a learning experience, and just takes time and practice with the skills. I recently picked up GNB and paused my PLD as my focus through SB/ShB content. Some things are 'universal' the basics of 1-2-3 and basic aoe aggro grab. Getting used to when to through the cartridge abilities between 1-2-3 combos or sliding one in between aoe's to help focus down one mob while keeping the trash occupied, has been interesting.

I know I'm a 'scrub' tank. I'll get you through any content I'm choosing to meatshield, but it will not be pretty. I'm going to use every CD, oGCD, and GCD to get you through; but damn is it not going to look pretty till I get comfortable with everything.