Loot drama. Sweet.
My take.. well, I've always favored guilds that use DKP systems, simply because in my opinion loot council only leads to trouble in the long run. Whether this is open trouble or back talking, stuff like that will happen.
As such, I also don't think selective loot council should apply. Suffering's End is a good weapon for any caster DPS that's able to use maces as well as healers (remember Naxx's torch, same deal). Why should anyone be excluded from using their DKP on it when it's a clear upgrade without any ifs and buts? They worked for their virtual currency and should be able to spend it any way they like within reason.
You can never predict drops. While a dagger and a sword may drop next week, they also couldn't drop again for 2 months, and no one should be told to hold out that long when the same stats they want on an item just dropped.
Also, bear in mind that every caster DPS can use two types of spellcaster weapons. Locks have daggers and swords, mages have daggers and swords, shadow priests have daggers and maces, boomkins have daggers and maces. Paladins have swords and maces, Shamans have daggers and maces. So yes, while every healer can use maces, every healer can also use another weapon proficiency that may have a similarly styled item available. Everyone gets two proficiencies that have useful one-handers. Fair game. (I excluded staffs here, obviously)
Suffering's End isn't a healer-only weapon or a DPS-only weapon, it's a caster weapon and should be treated as such imho. In Icecrown it'll be a little less muddled up since Blizzard is re-introducing weapon procs and you can make a strong case that a caster DPS should not get a weapon that procs on heal. Hooray for less drama!