With a controllable teleport ability one can teleport right into a closed door and reveal the other room, attack from inside the door, and move either way as desired. This seems okay with the mathemagic tree where this is quite high on the list, but with artful dodger, the second to unlock is knightly leap which seems overpowered this way. Basically, you can check for monster zoos on a level you haven't done it yet, even fight them, and when in danger just step outside, heal, go back, repeat. Is this intentional, or an error in need of a fix?
Hush! This is why we can't have nice things! Actually, I reported this months ago. Until it gets fixed I'm assuming it's intentional. This absolves me of the guilt of using this exploit. Heck, you can check for Lord Dredmor in rooms on floor 10 (or 15) and fight him the same way you're describing.
Forgive me for bumping this, after the recent patch I would still like an answer as nothing was changed and this question may have accidentally missed attention. I don't play with this skill tree as it feels cheap knowing that I may be getting an unintended advantage. Also, the forums seems much more active now, thus I may actually get an answer.