No problem, William.
The rule is there to prevent people promoting their own work in a discussion thread (not that Jim was doing any promoting).
Here is Alex's explanation.
People forget, and occasionally post amusing little ditties to emphasise a point they want to make, which is not a big deal in the great scheme of things, but we all agree to abide by the rules when we sign up. The staff are there to make sure everyone does!
Jayne