If all you want is a "pure absolute numbers without regard for all other important considerations," there are tools in place (like Rawr) to help you estimate that. Additionally, your statement that "my mage has 20k mana and never has mana issues" is mystifying. Total numerical mana pool is not the point, rate of mana depletion is- and good arcane mages have ways of spending mana faster than they can gain it, which is a DPS increase in the short term but a DPS decrease in the long term if you go OOM. That's the entire point of the milieu that you're responding to.
I see. My mage has 20k mana though, I rarely have a problem. Isn't the rotation with barrage in it the highest dps rotation? In which case why did the person a few posts above say don't use it?
This should not be hard to sort out, people. It should always be patently clear if item A is better than item B.. if rotation A is better than rotation B.. etc WHEN one is speaking of absolutes. This isn't always the case, no, but in THIS case it is, the subject is absolute highest dps, regardless of any other consideration.
Barring any other issues, isn't the blast stacking WITH barrage the highest dps rotation?