I have just been doing some arithmetic. The original lines in the song suggest that the unfortunate man with his testicles in a bit of a predicament is boasting of 1200 illicit encounters. My rewrite, influenced by fitting in a pony/ride double entendre, implies a much more modest 400 bouts. To preserve the proportion of the original, we should be talking of £8.33333...per go, which is difficult to fit into a fluent line.