The problem is Summoner has been incorrectly classified as sustain in truth their DPS works like this they have a slow ramp up then Bursts at their peak then after 4min they bursts around their bottom which is why throughout long encounters they lose DPS and it applies to all DoT DPS. SE should reduce the cool down on Enkindle to 60s and reduce the cool down of Aetherflow to 30s to bring Summoner in line with other DPS.