The problem is that they run too often, not that they are slow. mapStateToProps is called too often, and that leads to a bunch of needless shallow compares and

The problem is that they run too often, not that they are slow. mapStateToProps is called too often, and that leads to a bunch of needless shallow compares and often renders. Its a weakness of the magic design, and if I need to optimize the magic might as well just implement the whole thing.