'It would almost seem as if the more care and attention is applied to safety at work, the more unreasonable leisureable human behaviour becomes. For example there is the new threat of 'pogoing'. Once upon a time there was a craze for hopping about on a pole with two foot rests and spring- mounted foor which was called a 'pogo' - perhaps no more dangerous or idiotic than many other crazes (and with possible uses as a penetrometer!). Now, however, the idea has been taken up as a spin-off of disco dancing, ie vast numbers of people jumping up and down in unison - about as interesting as partnering a rammer, one would have thought. Apart from any damage caused to the human frame, this type of dancing is posing a structural threat to dance floors and related structures - possibly foundations. It is even possible that this destructive pastime was a contributing factor in the failure of suspended walkways in an American Hotel.' (Editorial comment in Ground Engineering).