Writing beautiful documents, guidelines and examples of best practice and hard earned experience is, relatively, cheap.
The cost of sending experienced, high quality humans out to a regional airport to train the staff embarking on a big project and then to monitor their project ...??? That takes long pound notes.
Knowing nothing about the CAA but a lot about living and working in the UK, I would wager that the CAA does not do that any more - if it ever did. One of the pillars of the temple was removed when Thatcher & Co implemented the 'Light touch of regulation'. They might have started with the likes of British Telecom but the path was set. Another pillar was removed when 'agencies' were created from govt departments and another pillar was the budgeting of said agencies.
Further, I would guess (note that I am mere pax and know nothing and I am GUESSING) that the CAA and others (not all) involved in UK airline safety (ground and airborne) are currently running on their reputation. That and the very hard work of the front line people who are keeping vigilant.
I hope I'm wrong but the law of familiarity will have it's way.