More than a few times I have been Head Cleric for my guild in PoHate/PoFear. In my group was the MT (Snoooooogan the pally) and Jarelorf the Wood Elf Warrior.
Jarelorf sometimes requests that I DO NOT heal him so he can get into super-uber-berserker-rage mode for extra DPS(Snoogan purposefully drops aggro onto him so he can take some damage a little bit at a time before redirecting the mob). I can tell he does a significantly increased amount of damage (duh, obvious), enough so that sometimes he tips the tables and our group becomes the EXP group in raids
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I agree with the earlier poster who said that Warriors do not have a way to dump aggro, and this can make it troublesome if the berserker warrior somehow grabs it. In my experience we have not had a problem doing this however; Snoogan holds aggro just fine, and it's my opinion that a Shadowknight's aggro would also be adequate.
Summary: Although it is a fun and different thing to do, I think it would be more work for you to explain yourself as a DPS-only warrior every time you join a new group.
I suggest making yourself a tank first and carry around a second set of "DPS Gear" for those situations where there's a shadowknight/paladin who is able to tank and secure aggro so you are free to DPS.