Necromancers "are terrible in groups"

[Feanol]

They can mezz, they can off-tank with pets, they can heal, they can heal themselves, they can root, they can charm, they can supply manna, they can split pull undead, they can ressurect, they can...

Necromancers are somehow simultaneously the best groupmate and the best solo'er far as I can tell.

Disclaimer: I have never played a Necro and have zero personal bias.