To be clear - they stated that Coil wasn't designed with healer dps in mind - and healers adding dps enabled teams to clear faster than they had anticipated. It was a case of players being better and more resourceful than the dev team planned for. It is very possible that they have learned their lesson, and Alexander could be tuned to need some healer DPS - we don't know.

There is something going on with the ACC tuning though, too. For instance with no acc capped down to 50, we miss a ton in those hard mode dungeons. But with no acc on gear we still hit over 95% in the current EX dungeons. It is possible that our actual ht rate in the Alexander with no melds can be the same as no melds (or relic) in Coil despite the actual accuracy stat being much lower. Here's hoping, anyway.