I don't think further restricting access to the flightdeck jumpseat will make the slightest bit of difference. Post 9/11 at my company you need to be employed by the airline and have a valid IATA ID card. Even then Captain's discretion still applies. If ID cards and aviation security in general are no longer a protection against terrorism then these extremists we unfortunately have in our society can get access to the aircraft before we even take our seats and jumpseat access is the least of our worries.
ES
