The fact that you have already argued quite a bit about a picture clearly showing Sammon to be around the same height as some teammates just shows how innately argumentative you are. Or was it an acquired skill nurtured by an argumentative environment? :)
There absolutely is such thing as innate aerial ability. Just because some players had it without having great skills with their feet doesn't mean it's not an innate ability. Nor does that mean it can't be worked on so I partially accept your point that he could conceivably get better at it.