I dissagree,
The chances of a terrorist falsifying an ASIC/Company ID/uniform AND being able to bluff the other 11-15 members of 'his' crew are bordering on bizarre.
Even if in the remotest of chances if he makes it to the cockpit he will have no idea of the company SOPs/procedures...even if he is type rated on the aircraft.
If an airline has a sleeper tech crew member no amount of screening at the terminal will pick him out because he will have been with the airline for years and have no requirement to carry anything suspicious on board with him...merely wait for the unsuspecting crew member to go for a comfort break or knock him out with the crash axe and use the pax restraint kit to immobilise him...and then lock the bullet proof door so no one can interfere with his plans.
The type of screening that aircrew are being subjected to at the present time is a criminal waste of resources.