More from Andy at Castrol:
"In the first reply I said that the EDGE Turbo Diesel was better in the
very latest ( 2006 onward ) diesel engines as these tend to have a
DPF -
you never even mentioned Honda in your first email !
The way it works is that the
DPF can be blocked by the metallic
additives in some oils ( such as EDGE 0W-30 ) so these are taken out -
so in theory, the additive package in the EDGE 0W-30 will be better as
the additives are still in there - and as your car doesn't have a
DPF
you can use the oil with the extra additives, which in theory, will give
you better protection - because the Honda doesn't have need for low SAPS
spec oils, we recommend the EDGE 0W-30."
So I'm going to have to change the Edge 0-30Diesel I bought for top-up to the ordinary Edge 0-30.