Too many situations would have to be programmed into it for it to not be complete garbage and it would be impossible to program for dungeons. You say it can maximize healing effectiveness…so it’s going to check who is using what defensives, what defensives/pots they have, and if those defensives heal then it will take that into consideration like a mage using alter time?
Reaction time is also important and so the GCD penalty would hurt healers a lot more than dps. I highly doubt they will even attempt it, but anything they make is going to be extremely awful and much worse than a human making decisions. Who and what heals you use is so dependent on what is going to happen in the future and we can be certain that it won’t consider that. How could you even program it to know that someone is positioned in a way that they are likely going to get hit by a frontal or swirly?