It irritates me when A/G ststions exceed their authority and, conversely, when pilots fail to recognise the difference between A/G, Flight Information and ATC.. .. .However, I must point out that Fenland isn't Air/Ground - it's "Fenland Information" and offers a Flight Information Service. FISOs can issue instructions to aircraft on the ground and use the phrase "at your discretion" to indicate to pilots that they are not subject to "control" by the FISO.. .. .Fenland isn't my home patch, but I've always found the service there to be provided within the rules.