Well last night I finally picked up my 4P item, so I now have Shoulder, Chest, Hands and Legs. I really wanted to get Head as it's better than my current head item... but I'll try work on that later :)
Basically this post is about when it's worth using the teir gear for the 4p bonus and when is it not. I have Spaulders of Catatonia which are best in slot, so it got me thinking about when it's worth not using the tier gear for 4P bonus.
I think my plan will be that while Tank Healing I will equip the tier gear for 4p bonus for the boost to nourish. As you may or may not know the 4p bonus for resto druids is a 5% bonus to healing done by nourish per hot up on the target. Now obviously on a fight like patchwerk a druid is usually rolling, Lifebloom, Rejuvination and Regrowth and hit Wild Growth when it's off cool down on the tank(s) (i dont think WG counts as a hot for these purposes but I could be wrong). So thats at least a 15% increase to the healing done by Nourish, sounds sweet right.
Now when I'm raid healing I do not have many hots on ALL the raid so the bonus will not be of much use at all. Without hots the bonus does not come into affect so I will most probably switch out the Shoulder for the better non-tier Spaulders of Catatonia. I will also look for a replacement piece for one of my other slots as 2 is as good as 3 with the bonuses, but only if I can get my hands on another item better than the tier gear.