This is incorrect. The page is somewhat unclear, but you are confusing the requirement for photo ID with the requirement for ID.
You do not need photo ID when travelling domestic. A BAEC card or company ID card is valid identification.
You do need photo ID when checking bags. A BAEC card is not photo ID, therefore does not meet this requirement.
If travelling domestic and checking bags, photo ID is required. The fact that BA staff do not enforce this requirement is another issue.
You are confusing yourself (and the OP).
1) There is no legal requirement for anyone to show ID (photo or otherwise) on a domestic flight in the UK. That some airlines have a policy requiring photo ID is as to do with revenue protection.
2) You don't need any ID to fly UK domestic on BA. We've had this discussion plenty of times and the BA web-site categorically states as much, so the comment about a BAEC card or company ID card being "valid identification" is somewhat moot.
http://www.britishairways.com/travel...n/public/en_gb
3) As far as ID for checked bags is concerned, I've personally checked bags numerous times and never had to show photo ID, and furthermore have been told categorically by BA staff that a BAEC card is sufficient. Not sure where your info is coming from unless you work for BA?