A wizard with maxed AAs, Demiplane+ raiding gear, and that LoN necklace thingy could probably beat an equivalently geared necro. The problem with raiding guilds and DPS like that is that for a wizard to get more DPS, it's about how much they can control agro -- for a necro, assuming that you know how to manage mana (or have a big enough mana pool to handle it), there's not much of an option to increase DPS without just chaining as many dots as you can. Any time that a necro gets resists on fire, they're going to suck asshole on DPS...poison resists or magic resists would give similar effects, but not as bad. Because dots are all or none for your mana, as opposed to nukes that are normally all or partial-damage-for-your-mana, wizards can jump necros on mobs with nasty resists.