I'm noticing tanks are having a lot of issues when taunts need to be called out or explained. My tank and I in my ten-man group communicate taunting with each other when it's a matter of preference, but for things like Stone Guard tanks should be able to know when and what to taunt without having to communicate it.
Stone Guard is actually really simple. but the way the information is conveyed to tanks is what makes it confusing. The ONLY time a taunt EVER needs to happen is:
1. You are tanking one Stone Guard, the other tank has two of them.
2. Your Stone Guard is the one which just began petrifying. This is easily indicated by a bright ring appearing beneath the dog.
3. If 1 and 2 are both true, taunt the dog which recently overloaded.
There should be no other reason to taunt during Stone Guard.
I have only done Normal mode MSV, but the only difficulties I have as a tank are the sheer damage outputs given by Elegon (that stupid breath) which can be easily negated by Frenzied Regeneration, and Will of the Emperor. WotE is actually a very easy fight to tank, but it's very unforgiving if you slip up while tanking (getting hit by a single devastating combo attack is a double-whammy, as you lose armor and you take a big 100k hit). Additionally, the two constructs that you tank during that fight can really easily mess up your movement with that stupid persistent death grip debuff and their obnoxiously large size making them uncooperative when moving them.