The question is whether “Readback Correct” amends a verbal clearance.
The scenario: The pilot files a flight plan to KXXX with the routing AAA dct BBB etc. At a non-towered airport the pilot receives a clearance by phone.
“N123AB is cleared to KXXX via direct CCC direct BBB then as filed …”.
The pilot reads back: "N123AB is cleared to KXXX via direct AAA direct BBB then as filed …"
The controller replies “N123AB readback correct”
The pilot takes off and flies to AAA then contacts ATC who reply “Possible pilot deviation, I have a number for you to call advise ready to copy”.
In this scenario the pilot is obviously at fault for an incorrect readback and the controller is at fault for not picking it up but does the term ‘readback correct’ act to effectively amend the clearance.
My advice to the pilot is to file an ASRS and be prepared to eat humble pie but I'd be interested to know how the FAA will view this.
That was decided long ago in Administrator v. Merrell. The pilot is responsible for getting it right the first time it's read. Only if the controller read it wrong originally is the pilot excused.
Do file the ASRS so there's immunity from sanctions (suspension or revocation), and so be polite and cooperative with the Inspector so you come across with a “positive compliance attitude” and you'll likely get off with an administrative action like counseling or a Warning Notice, but the controller's failure to catch the readback error won't get you completely off the hook.
BTW, that controller is also going to catch flak for his/her failure to catch your error, but they won't talk about that with you.