Mad Jock, you are probably right that the Mil AIP should be more accessible but a lot of the relevant bits including mil low flying information are available through the CAA. Getting GA pilots to read this
http://www.caa.co.uk/docs/33/ga_srg_...18November.pdf for example and to use the Civil Air Notification Procedure would help everyone. There is current low flying information on the HMG website as well
https://www.gov.uk/low-flying-in-your-area so a bit of planning should go a long way.