I've had a similar experience which I recently posted in a thread: Burst vs. Sustained DPS.
The elemental shaman code base does not seem to be as far along in development as some of the other modules. I believe that a new developer has recently joined the Rawr team and has been working on the Shaman code bases, but I imagine it will take them some
time. A few impacts:
1. The burst vs. sustained DPS slider seems to be "junk" (i.e. provides no useful data). I have mine slid over to 100% burst so make the #s easier to read
2. DPS/simulation calculations do not include some of the "real life" modifiers that some of the other modules provide. Latency can have a substantial impact on DPS especially when you have higher amounts of haste. Some of the modules are even
starting to incorporate encounter specific calculations (i.e % of time moving). This of course has no relevancy for training dummies, but is relevant for real world usage
3. I am personally skeptical of the algorithm/math/etc from the simulation DPS (I think that the numbers are high above and beyond what is listed above, but I have no hard evidence of this.. just my opinion ... so please take that as such!)
One other sanity check I'd ask of you is:
Are you simulation #s based upon buffs that were not present for you when using the training dummy?