The attachments show lines of folded hull with 1m nose blocks.  I also analysed nose blocks of 2.5m to show how they compare with the shorter blocks and the smooth lines.

I narrowed the hull to 440 on the bottom and 500 at 600 high as the block coefficient increases with the folded hull.  That gave roughly the same draft for displacement.  The comparison of these different shapes are all at 1000kg displacement.  So the Black is original smooth lines, the Blue is 2.5m ends and the Orange is the 1m ends.

Compared to the smooth lines the nose block causes additional wave formation.  This is something I have observed on the 18m proa.  The wake is more confused than what I have observed with other slender hulls have smooth lines.

There is a not much difference between the continuous curve and the 2.5m block ends apart from the low speed range.  By contrast the 1m block add drag throughout.   

There is a variation on the folding system that avoids the block bows.  Rather than having parallel foam panels in the layup the three panels that form the bottom and sides are all cut to the shape required to form the sides AND the nose, laid up as flat panel then the glass trimmed in the wedge where the panels taper to leave enough glass to overlap on the chine seam that runs from where the panels start to curve all the way to the stem.  That means the straight part of the hull is folded per the simple method and the ends are done in a similar way to stitch and glue.  I have used this method on model boats but not yet on something bigger.  

In my view the gain in longer tapering ends is worth the effort over short transition from the stem to straight portion.  The 1m ends would have a measurable loss in sailing performance in light winds.  At 6 knots the drag is double that of the smooth lines.

Rick