This post was brought to my attention by a FC member and we started discussing what mechanics should be practiced and understood better by the FFXIV community as a whole:

1) Tethers - Understanding when to break them or when to stay close to your tether partner. Also tanks taking tethers off of squishier party members.

2) Tank swapping - This could be an entire section just to understanding how to pull an enemy off another party member in general but then expand upon instances where it must be done due to certain debuffs (ie pull boss monster off of dummy tank when it gets three stacks)

3) Divebombs - Once again this could be elaborated upon understanding certain marks upon party members during a raid and adjusting accordingly. To my knowledge divebombs have a specific symbol that's remained consistent through 2.0 and 3.0. With more dragons on the way I imagine we'll be seeing plenty more divebombs in the near future!