"GA Driver, a long briefing can take the form of guided study"
Thats what a initial long briefing should be but it should take around 45-90 mins depending on the sequence. At the end of the day , the instructor should be satisfying themselves that the content is covered in full and the student understands said content.
20 mins chat and lets go flying never has and never will cut the mustard.
Not a real fan of guided study in any case (at least for the ab initio sequences).
"If I had to sit through an hour long briefing every lesson I can tell you right now that I wouldnt be able to do it"
Not before EVERY lesson. Just the initial sequences, and the first time at that particular sequence at that.