MoI's implementation is a much better way of doing it. Just start using it and you'll see why Michael did it this way.

That is what makes it so cool: No gazillion drop downs to navigate, or dozens of key-combos / multi-button presses to use it.
Much more ergonomic and efficient.

Plus, only a few buttons to ever memorize. You can always click on an empty space to deselect, use invert, use shift, drag a window (left-right, right to left are different) and so on. Pure effort saving implementation for ease of speedy use and modeling. Especially if ones uses a tablet.