I can understand that it would be disheartening for a few because they would find the mechanic stressful. Inevitably, though it is simple math, everyone thinks differently and some take longer to calculate these sorts of things. However, the truth of the matter is that a majority are able and this is completely optional content. Nothing is really necessary from this raid; it's side content for people who may enjoy it or are too impatient to grind for mendacity tomes, as I understand. If you aren't a fan of it, then you don't have to run it. I personally love the mechanic; I think its a fun to have to pause and quickly think out a small problem in the middle of the fight.