Originally Posted by dnseal
Question, to which I may already know the possible answer....
Why run the bitter end of the single line reef line ....back down to the boom? ...
You need the turn on the boom so that the foot of the reefed sail is properly tensioned, the foot gets shorter with each reef. The termination of the reef line on the boom in effect provides a new clew, at an appropriate location for the length of that foot. The reefing line needs to both pull the reef point TO the boom while also tensioning the foot
If you did not connect the bitter end to the boom, and you were trying to trim the leech reefing point out to the normal clew location at the end of the boom, you'd run the risk of ripping reef point right out of the sail, or at best the main would have a fat and not so funny shape.