15% more damage for 15 seconds. If dps is 2189 then damage over 5 minutes is 656700.
15 seconds = 32835 damage so without inspiration that would be 28552.17 damage giving a difference of 4282.8 damage. This leaves the total damage at 652417 over 300 seconds giving an average dps of 2175 which is still first place
Please correct me if I'm wrong
Granted this doesn't take into account the fact that during inspiration the damage output is probably a lot more than the 32k damage i used.