The iconic necker has shrunk thru the years. My sources indicate the original BS necker was about a 36" square, folded into a triangle, gathered, not rolled, and held on the neck (over the collar !) by a hand made woggle. It was intended as a tool on your uniform, which, after all, was worn to ALL Scout events, and often to school , around town, etc. One might wear the necker just because....
It had many uses, I have a book that lists more than 50 ! Dust mask, horse bridle, signal flag, arm sling, pole lashing, ankle brace, tourniquet, bandage, sun hat.......
The necker of my yoooo