It depends on your experience with the job, the dmg heaviness from mobs in the duty and your gear.
I have been whm main over 5 years now and I sometimes get tanks..gnb inclusive, who need little to 0 healing in a wall to wall pull. If I see a tank who mit well, don't drop hp too fast, and mobs who will die before the tank can reach 0hp I won't heal if I don't have asize or a lily I have to uncap.

I do not believe in healing someone who does a fine job healing themselves so for me... if my tank can handle themselves it's a huge plus.

I also believe it raise a players class experience and technical flair that they get a chance to relly on their own toolkit more than on mine, so thumbs up for wanting to experiment with being self sufficient in pulls.