OMG they are maybe one of the most CRAZY and wicked ways of getting stoned. I find anyways. But if you do them for the first time, have some water or something cold to drink by you. It tends to burn your throat. You get use to it fast thou. The first time I did it, it took me by surprise.

To answer why it gets you so messed up...well truth is I don't know for sure. I assume it is because you are taking the smoke and if done right there will be no waste what-so-ever. So really you get what you roll.