Whats important when reefing is the ANGLE that the resultant stress makes with the reduced sail .... much like the same exact function of moving a jib fairlead car back and forth along the genoa track.
The 'plain vanilla' attachment point for the clew reefing line should be adjusted so that both the tension along the foot and leech of the reduced area wind up with 'equal' tension. A sliding cheekblock (for the reefing attachment) on the boom is the best way to get the angle correct ... and the foot/leech not unduly overloaded. If this arrangement isnt correcting the amount of heel to a comfortable angle, then reef 'deeper' !!!!!!!!! instead of the potential of 'busting' a sail by over-tensioning an edge.
From the attached pic below, you want the stress to pass through the centroid of area in the reduced sail area ... this will ensure equal stress along the leech and foot edges for
good sail shape as the sail designer intended (even when reefed).
How to find the 'centroid': divide each 'edge' (foot,luff,leech) in half and draw an imaginary line from the 'corner' that is opposite of the 'side' ... where the three bisecting (dashed) lines meet is the 'centroid' ... and thats where if a single line (solid blue arrow) would 'point' if there was only one single reef line at the clew.
Most who reef seem to grossly 'overdo' it.
1. sail area reduction by reefing will decrease heeling
2. over-tensioning the outhaul will cause a FLAT shape in the bottom sections ... and that will leave one with little 'power' if needed to 'punch' through waves ... youve reduced the area but have left the sail SHAPE in 3rd or 'HIGH gear', when sometimes you need a lower / 2nd Gear for the 'punching'. Over-tensioning of the foot (by outhaul) will also 'relax' the leech which makes it vulnerable to 'flogging' because its now 'pointing' too far to leeward --- a good way to rip/shred the stitching if it starts to flog especially when tacking.
On most boats if the amount of heeling is still not under control when putting in a first reef ..... simply reef deeper (2nd reef) and 'ease' the 2nd reef outhaul to provide the needed draft to keep the boat 'moving forward' with more power lower down in the sail ... much better than having a FLAT reefed sail that doesnt have enough power and that cant accelerate out of a tack or a boat thats constantly being stopped dead by large oncoming waves.
Tying in the reef points .... loose, so that the stretching sail can 'move' and you dont pull out the cringles. For a 'first reef' I hardly ever 'tie in the bunt' .... I just let it flap or very 'loosely tie in the areas a-flapping' if sailing 'short legs'.
Strap across the reef clew, isnt really necessary and may adversely affect the 'direction of tension to the centroid' of the reef clew line. On reefing set ups with fixed cheekblocks on the boom usually results in too much tension along the leech and then you have to 'play' with the vang to make the corrections so the leech doesnt get 'over stretched'. If you NEED a strap across the reef's clew, you probably have the WRONG position on the reef-line cheekblock and it should probably be moved forward ....but then again most who reef overtension the foot of the reefed section !!!!
