I only learned about the 'french fold' technique about 2 months ago. I first saw it demonstrated in the Julia Childs Baguette video (link posted elsewhere in these forums).

Said video shows a rather energetic Danielle Forestier lifting dough above her shoulder/head and smashing it down on the work surface before folding it over and repeating (800 times allegedly!).

What I've discovered is that when I use a slightly gentler technique, the dough (gluten) actually develops quicker.  Rather than smashing it down, I lift the dough about 10 inches off the surface and 'lay it out' as if I were laying out a rug or carpet (initial motion forward quickly followed by pulling back).  I then fold as per usual and pick up at the side (essentially giving the dough a quarter turn) and repeat as required.  For me this develops that silky smooth, window-pane-passing dough more swiftly and with less of an armache afterwards!

Anyway, I don't know exactly how or why this works better for me.  I suspect I had previously been tearing gluten strands through over-zealous dough-slapping. 

Hope that helps

Cheers 

FP