Agreed.
With a good party, SMN dps will be lower due to less time for DoT's to tick on Ravana before he changes phases.
With average/bad parties, SMN dps will be top or 2nd highest at least due to longer time for DoT's to tick.
For Ravana EX, I cannot out-dps MNK/DRG/NIN if kill time is below 7mins. However I will be king if the kill time was above 8mins since I get another round of RS DoT's out.
Biggest conundrum of our job, we do better the worse our fellow DPS are and vice versa.
Also would like to see the video of the kill, I'm interested to see what your SMN was doing and how it differs with what I do.