While using Skada and Recount the calculated dps is simular to picoDPS while solo (target dummys). However, when in a raid setting it seems that picoDPS is not valid. It seems that the dps is half of what skada and recount are reporting. Will try and post screen shots.

DPS all depends on how the addon determines when you are in combat. Are the total damage numbers similar?

Here are some numbers... All from training dummies (not sure if that skews the numbers)

round 1
260dps 3909 damage (reported by pico)
340dps and 2k damage reported by skada.

round 2 (a little longer fight)
561dps 22895 damage - pico
559.3 ~14k damage - skada

It seems that a longer fight the DPS was a little closer but the total damage is way off. Now I was testing on a warlock alt and it seemed after I was out of combat that the dot damage was still being tracked and my dps was being updated. Not sure if that gives you anything.

I only did a few tests and unfortunately dont have any combat started and end timestamps as neither of the addons report that (or at least total combat time).

Did you have a pet present for this? Pico includes pet damage in the owner's totals

Yes I did. I have a raid tomorrow night and will do some WWS parsing for some hard numbers. Ill screen shot the picoDPS reportings as well.

Couldn't get the /combatlog to work (the resulting wow log file was empty). So I wasn't able to get a parsing. However after some hardmode attempts I was looking at our dps. It didn't show any one over 2.8k dps. Recount and skada reports were showing members over 4k. I will try to get a parse working tonight.