On a short gathering session I encountered two types of gathering Bots in the game.
The first type is invisible, you know he is there because you can hear the sound of the node being gathered and if you are in the right spot you see a name appear briefly (usually some random name like mfgprt).
The second type appears out of thin air at the node, gathers it and disappears again, only to magically appear a short distance away at the next node to gather that one, and so on.
I hope steps are being taken to deal with these types of exploits. Clearly they are the work of cheaters and gold-sellers, neither of which are a welcome sight in TESO.