Heron
Did you ever wonder why Heron was willing to spend most of his life with a dragon, hiding his own intelligence from the other dragons? Or why Grabon was willing to do the same among the humans? Why did claiming the territory change all of that?
Well as far as Heron hiding his intelligence from the dragons, if one of them had felt that he was too much of a threat before Grabon was large enough and skilled enough to help him, they could have both been killed, but also a territory dragon may well have insisted on keeping Heron to study. I think the idea of that gave him the willies. As far as Grabon? If he had revealed his intelligence without being in control of the territory, would the Farmers have accepted or rejected him. Would they have wanted to exploit his skills? What position would that have put Heron in among the only humans he associated with? His friend Gordon may have suspected that Grabon was an equal companion to Heron, but he never told his relatives and he never openly acknowledged it. They all knew that humans do not share the spotlight well; especially not the superior spotlight.