I used to see it that way as well, but when I discussed this in another forum, some people pointed out that Teleport is a spell linked to the Movement rune, and so what it actually would do is to transport you to the other side of the Warding, which would mean you actually do cross the boundary, and therefore must suffer the consequences. From this POV, when using the magic of Mastakos, you are emulating the god, so you are actually moving lightning fast (even if in spirit/air form or whatever), not just disappearing into the ether and then reappearing somewhere else.