Just returned from PFO (passenger) and cannot for the life of me see how two pilots can each / together mistake the taxi way for the runway under any circumstances. From the ground and from the air not to mention a chart for reference it just seems impossible.
No markings on the taxiway whatsoever - clearly visible runway markings - piano bars, numbers, centerline and heavy tyre marks all down the landing areas of the main runway from the passenger seat after departure and turning downwind at 3-4 miles - even if not visible on approach from far out surely to god clearly visible on short finals.