John and Martha are not now, nor have they ever been, professional pilots. I realize professional is an attitude, not a paycheck, but they have never had a real flying job. Sure, they fly their jet all over the place, but they've never HAD to go and find their way through the weather, they've never HAD to make a schedule, they've never HAD to cater to the whims of passengers. When they wanted to fly a jet, they didn't have to compete with others for a job, they just went out and bought a jet. They have never really given any substantial amount of flight instruction, either. Their forte' is in ground instruction.