We're all aware that there are far more challenging approaches around the world than Oban. The implication is that it would be difficult to licence an instrument procedure without serious public transport performance degradation in terms of the runway length available, clearways etc. Realistically, I don't think a schedule would survive from a consumer support point of view; and even then without lengthening the runway it would be limited perhaps say to Twin Otters or Islanders. (yes, I am perfectly aware larger types such as C130s have been in without problems but they are not regulated in the environment public transport is).