In reply to Oceanrower:
Correct Nigel. I found the bolt while showing some cavers how to find the cave. I was pretty surprised to be honest but not disgusted until I thought about it. I have done a lot of rigging of vertical caves and generally don't give a f*** about putting in bolts but only IN CERTAIN SITUATIONS, the underground environment is often chossy and rope rub must be avoided at any cost. Saddle head is clearly not choss. I can see why this caver has gotten into the habit of indiscriminate bolting and probably did not realise the caridnal sin they were commiting (how many non climbers are going to know there are no bolts in Pembroke).
Of course its totally unecessary, there are heaps of sling placements, a stake and even an old spit in the area. I shall post something on UK caving and remove the bolt on my next trip in that direction. Unless there are any major objections?
Dickon