(1) you won't find many professional potters potting in the shipping lanes (M3) - because their ends just keep getting cut off.
(2) I believe lifeboat was responding to those suggesting that all potters were at fault etc and subsequently (to that post) clarified.

Generally I am of the view that the local harbour aurhorities should do more to ensure that navigation is safeguarded in those areas under their control through byelaws and enforcement as already commented on.
In open water that secrecy should be put ahead of safety is however ridiculous.