I mean, they say in their forum profile they're a tank and DPS main who finds healing challenging and only have WHM at 90 and SGE at 70 (probably either just unlocked or is just sitting on it because it was "too challenging" for them).
If their only healing experience is the sub-par WHM plus their 7 years of WoW, it makes sense that they think all healers are/should be heal-princesses. :B