Only for IMC holders when IFR in Class D or G airspace
OK, I should have quoted a bigger piece.
I think IMCR holders are stuck with the 1800m min met vis on any IFR departure or arrival, no matter what the airspace class is.
Do you have a reference for lower permitted forward vis when operating at a Class E or F airfield? That would be serious news to me. Doesn't affect me (have an IR) but interesting nonetheless. I know there is very little E or F in the UK...