I'm not going to use my experiences to provide reasons why you should just go outside, I'm just going to say this: It's safer. Oh, and the incense will cover it thing if you drain it, the incense has nothing to do with it. If you truly "drain" the room then it won't smell anyway. The hard part it to truly "drain" it, smells linger, and even if you light incense your room will smell like pot mixed with incense. Discerning noses can still tell, just like if you blow pot though a doob tube it doesn't smell like dryer sheets, it smells like pot that has been through a doob tube.