Bar shaker,
The pilot in question got a reprimand for breaching Rule 5, but no other penalty. 2 years later he was permanently grounded for a similar offence, this time he flew under an 11kV power cable whilst beating up his house.........................
The whole issue of low flying is frought with interpretation which does not get set into legal precedent, usually because the cases are not often heard in a high enough court.
Add in the fact that the CAA are often seen as vexatious litigants and you have have a right dogs dinner with regard to interpretation of the law in this area.