safetypee, the words are indeed from the AFM. The actual quote is:
Originally Posted by Performance Section, BAe146 AFM
Dry runway
A dry runway is one which is neither wet nor contaminated. For performance purposes, a damp runway is considered to be dry.
It then defines a wet runway in much the same way as your EU-OPS quote.
The page was amended in 2007 so unless there's been a subsequent amendment that I don't have, those are the BAe words on a damp runway as approved by EASA.
Standard caveat: "legal" does not necessarily mean "safe".