Taking the back over the heel button is structurally excellent - I do it quite a lot. String tension makes the neck a lever, trying to pull the base of the heel away from the body, and this resists that pull at the optimum point.
I suggested the dowel joint might be less than good because I've come across quite a few failures with that joint, and also because repairers tend to curse it as it makes dismantling a partially failed joint more difficult.
As I understand it, the dowel gives you very little long-grain to long-grain glueing surface, particularly if the dowel is a sloppy fit, and it doesn't do anything to hold the base of the heel against the body, which is where most separations start.
I have no practical experience with dowels, which is why I wrote "perhaps". But if the dowel isn't adding anything useful to the joint, why go to the trouble of including it?