It is easily possible to hit 800+ dps whilst also buffing your group, I have hit over 900dps on static fights such as gruul (movement isn't great with trinkets/racials running), I've included a link here
http://www.celebrityguild.com/forum/...607-0004/index to a WWS of a Void Reaver fight where I spent most of the time dodging the arcane orbs (I had 7 targetted on me during this fight, a couple came in a row and forced me to run quite far from the boss) as you can see I was pretty much using Chain lightning on cooldown, when I was in range and not running! Considering the gross mana cost of this spell, it doesn't do much more damage than the average lightning bolt. My advice to any shaman with mana problems of any kind is to completely disregard this spell for DD as it really isn't worth the slight dps/damage boost it gives. In regards to 'gear' I am slightly over the hit-cap (ok, maybe a bit more than slightly 17.5% with totem/talents, still looking for gear to swap out), I have just under 42% crit and ~1100 nature damage buffed with totems and talents. On our guild website, there are WWS reports for other fights. Comparing myself to Conando in the above mentioned 1000+sustained DPS in the Kael'thas fight, I must say in my defense my dps/dps-time was low due to the fact it was my first time at the encounter, and also forgetting to oil-up my weapon. :0)
Incidentally, I would suggest using Brilliant Wizard Oil
http://www.wowhead.com/?item=20749 instead of the Superior Wizard Oil
http://www.wowhead.com/?item=22522. The reason for this is 14 crit rating (slightly over 0.5% crit) is much more useful than the +6 spelldmg. Sorry to go slightly off-topic.