To make an aforementioned note, they don't control Dragons. There's no slavery, no control involved, and under jurisdiction (within reasoning) warn a Dragon of an incoming threat (with RP knowledge, of course) so it may fly away. They can using a pure telepathic speech free of language barriers and more so focused around intent, will, are able to pacify Dragons. This is a means to maintain and upkeep the Dragons they make, giving involvement, which is done through using Aruzond's powerful draconic voice recognized by Dragons as its the voice of a Greater Dragaar. Any sort of Dragon relocating to an area with populace can only be exercised at will of the LT, meaning if the ET wanted to do something, then that could coordinated to provide a Dragon event like Swgrclan did with wood elves and the Jackal Dragon. The whole grove event line for the most part was badass, so its to allow anything like that to happen at moderation of the LT, and ET.
Otherwise they're useless in terms of exercising Dragon power because that wasn't the marshaling thought around it, just to give events seen by ET and LT moderation when wanted.