I could buy into healing being a problem...but from experience, it's more than that. Granted, both V5S and V7S have a bit of randomness to them (more so with V5S), but it's unfair, in my opinion, to place this all on healers. Tanks and DPS have their own fair portion of the blame as well, from not doing what they're supposed to do either. As a tank, I've been able to Holmgang the Head-On, granted my healers know this ahead of time and can prepare for it. I wonder how much communication, or a lack thereof, affects these runs too. When I run V7S, I always assume ink is coming out and move away from the boss (depending on role)as a lot of PUGs don't really communicate in that fashion. It worked out for me, until I learned the exact timeline of mechanics.