What is the relationship between an Air Traffic Control clearance and the Pilot in Command's ultimate responsibility for safety under ICAO Annex 2 and RAB 91?

1. An ATC clearance is an authorization to proceed under specified conditions; however, the Pilot in Command remains solely responsible for the safe operation of the aircraft and compliance with terrain avoidance rules.
2. An ATC clearance relieves the pilot of all collision avoidance responsibility.
3. ATC clearances are voluntary recommendations that pilots may ignore without notification.
4. Controllers are legally liable for aircraft weight and balance configurations.