Most of my fps time was spent playing a CoD:UO, CoD2, CoD4 tactical realism servers. They usually had rules such as no firing unless you see an actual uniform (seeing tracers means someone is shooting, not WHO is shooting) to avoid team killing. Similarly, we have no throwing blind grenades (throwing a grenade without actually seeing anyone there). Anyone who has played RO1 knows how many team kills blind nades cause. The only time blind grenades were allowed is when you were clearing a room, which limited nade spam a great deal. The only problem is Tk's still happen during room clearing on occasion because lets face it, pubs are not the most organized. With the new honor system I really hope it'll be a sort of psuedo prevention method for nade spam in pub servers. Really helps improve the quality of gameplay in my opinion.