Using HPS as a metric is horrid. There are runs in +8s where the healer pumps out 800k+ overall and +13s where the healer does 500k.
So yes, it is poor play if you are going oom. You are spamming WoG and most likely letting SoTR fall off because you are using up Holy Power for WoG among other glaring issues for why you are taking in so much damage.
This is 100% a skill issue. How is it that I have never stopped to drink from +2 all the way to +13 while you are going OOM on the 2nd pull?
It literally did not have a significant impact.
https://www.warcraftlogs.com/reports/atX49mnhpFLvf8JP#fight=3&type=healing
+10 NW healer with 415k overall HPS and 36.85% overheal
https://www.warcraftlogs.com/reports/TnzktVWhGfgwQ71v#fight=7&type=healing
+10 NW healer with 485k overall HPS and 46.09% overheal
https://www.warcraftlogs.com/reports/BZg82TaFfRCz7wKP#fight=1&type=healing
+11 SoB healer with 558k overall HPS and 56.34% overheal
https://www.warcraftlogs.com/reports/Wv7AK6gzF4THwL3N#fight=6&type=healing
+11 SoB healer with 656k overall HPS and 39.01% overheal
https://www.warcraftlogs.com/reports/CXAaYy1W8cZKTgHQ#fight=3&type=healing
+10 Mist healer with 390k overall HPS and 46.76% overheal
https://www.warcraftlogs.com/reports/HkQwr9ZbBf8mcvyD#fight=92&type=healing
+10 Mist healer with 499k overall HPS and 43.13% overheal