J --- I thought the same thing from looking at the picture, but there are actually two separate wires that are several inches apart. The wire around the post connects the chicken wire to the post, while the wire going up from the insulator is a couple of inches in front of the post and is going to another strand of wire on more insulators circling back around to complete the circuit. (I should have been more careful with my photography, cleary!) You're totally right that it would be a very bad thing if the electric wire wrapped around the chicken wire, but luckily this isn't the case.

Heath --- These K9 units are supposed to be special in that you don't have to ground them. I don't entirely understand how that works, but that's what the instructions say. Yup, all yellow insulators.

Dave --- Hopefully it's still enough to get Lucy's attention. It's less than it was previously, by Mark's tough-the-fence-and-swear meter.

Heath --- I'm not sure if she's been bad enough to test it yet. But no new holes, which is a good sign.

Disconnect the energiser from the fence and test between the terminals. This will give you the output energy available. Anything under 6000v is a bit rubbish. If the energy drops when you've connected it back to the fence then the fence is the problem. This is a link to a step-by-step sequence to check a fence. http://www.agrisellex.co.uk/information/trouble-shooting.html