Guild Wars 2

Hey! I’ll be raiding with guildies from hereon, we’re attempting gorseval and I hear there have been kills with 1 class being the tank and healer, also namely the druid which Ill be playing as.
I was wondering if anyone could give some pointers of what the druid tank (or tank in general) has to do in VG and Gorse, and is your impression that it is “doable” and most optimal having this in one class? I assume this would also require more of the individual player kitten far Im finding myself healing quite constantly (due to others mistakes).
I am familiar with the raids basics, but since everything is so new I’ll gladly take advice/tips.
It would mean I’d have to change my zealots into clerics, but one for the team i guess.

Thank you for your time