Archonix has posted that Trion are taking a look at a variety of mechanics in Nightmare Rifts and will look to tweak some of these in the coming weeks.
For now, Maddening Shield and Maddening Heal have been disabled. These are look-away mechanics that would shield or heal the boss. No ETA on when or if they’ll come back.
Note: The red circle shielding mechanics that some adds and bosses have still exist.
If you ever wanted to get a little further in open-world Nightmare Rifts, now’s probably a good time.
RiftGrate 
Not sure how to feel about this….. would like to see the mechanic kept in instances but in open world I can see it being removed being a veeeeery good thing.
In the French version, “Turn away” has been translated as “Écartez-vous” which only means “Stand back / Move away”
It resulted in very few people knowing the mechanic and was almost impossible in open world to beat a boss using this. Maybe that’s why they removed it ? Correcting the translation would have been quicker.
A great change, overall. 🙂
I liked the ideas to make it a 1 shot mechanic, and a 2nd or 3rd fail would cause a 15 minute “duncecap” debuff. So glad they disabled it- I’ll do open world NMRs again now.