Of course it's safe. Stone does this with people all the time, back home. It's pointless to be the biggest, strongest, and most steady if you can't use it to carry wingless Arbora or groundlings, or tired and injured warriors. There's even a ridge of raised scales along his collarbone, which would make really great handholds when flying, or in the case of someone as big as Stone, almost a sheltered seat.

He taps them with one claw, makes sure Rosinante is holding on to one, then rises up to two feet, wings half-spread for balance. One could see pretty far, from there, if there was anything to see but lanterns in the distance, and the glow of the lighthouse.