I've actually known of this easier way to get to Karazhan before Cata launched, and unlocked azeroth flying, though back then it was just a theory. I've included an easy Tutorial in my recent video, I apologize if the video hasn't fully uploaded and is not ready for viewing.
In that case, wait. This is also for the people who really don't have a fishing chair or a toybox saber.
To note, I did search before posting, but I did not find this route to the Crypts. Also I ALMOST overshot it in the video, do not be like me.
Song: Down by Scandy
---------- Post added at 06:40 PM ---------- Previous post was at 05:30 PM ----------
Yes, I realise my post is beating a dead horse, but I just wanted to point this out.