I heard one guy today being warned off the LHR zone. His answer? "We're right on the line according to my GPS".
Are you sure he didn't mean he was exactly on his pre-planned GPS track rather than on the boundary line?
Modern GPS is reliable and accurate. You'll be happy to learn that the CAA are finally beginning to accept that fact! The astrolabe and quadrant-staff dinosaurs are beginning to be put out to pasture.
Can anyone tell me what is required for a GPS to be 'IFR-approved'? Does that simply mean that it may be used for approved GPS approach procedures? If so, it is a misleading description - navigating above 8/8 cloud in VMC with a 'non-IFR' GPS is surely legal, so why not in IMC outside CAS?
More and more people will prefer to navigate
purely by GPS, particularly given the poor reliability of many Club a/c avionics boxes and the forthcoing decomissioning of VORs and NDBs.
Map reading, so beloved of Mr GASIL, is a dubious way of navigating in marginal-yet-legal VFR - a modern GPS of any description is far more accurate and will, if used correctly, be much better at keeping GA pilots from CAS infringements than the Mk 1 eyeball.