'eits' - I suspect the CAA may see things differently now and perhaps the AIP has yet to 'catch up'?
A recent CAA pamphlet (cannot quote the detail) advised that RODs of less than 500fpm (in the approach phase) were 'OK' in order to achieve the required CDA profile - as 'hotmetal' says.
9 times out of 10, if one takes the instruction 'descend altitude 3000' and further with the glide' as 'descend now', and flew 500 fpm, you would require power to fly level at 3000' before the GP. I am flying less than 500fpm iaw the pamphlet and achieving CDAs