[quote=@Alphakoka]
<Snipped quote by Tasuke>

generally, poisoning, preventing healing, make them unable to rest, probably stealing something of theirs, anything but direct attack. So something like stabbing in the back is probably not allowed.
[/quote]

These. 

Most the time it wasn't used, as mentioned, due to the lack of space between fights - so really - only the people finishing up quickly could make use of it. Sort of adding some sense of urgency to the fights. Another reason is because people seem to have an innate sense of when their shit is fucked with. Barely anyone eats after someone, rooms over, messes with the food somehow. 

I didn't find them boring though, then again, I've went into fights with obvious injuries, and been into a fight without any abilities(Sans one), or weapons.