advice, but not policy? i guess the question is would you refuse to appoint a ref who insisted on wearing glasses rather than contacts?
I am continually suprised by various posters who seem to want Societies to issue edits, policies, and instructions. You completely misunderstand the role of a Society and how they are run. Also many people, including the Executive paid staff at Twickenham, seem to not understand the respective roles of RFU (as home union), CBs and Societies in England anymore.
We are the elected volunteer Committee of a volunteer organisation working with, and for the benefit of, our membership to provide suitably trained and competent referees to all matches in our county, ensuring we and our members execute duty of care, and above all safety, to all involved.
Hence we give advice and guidance, not orders and instructions.
In answer to your question "would you refuse to appoint a ref who insisted on wearing glasses rather than contacts ?", I have no idea as we have never faced it in the last 10 years, and so we would have to discuss it at Committee if it arose as an issue, consider the level of match, safety implications, and approporiateness of wearing glasses at that match.