Thanks, Yoav. My "lame" is pretty lame, really...lol...just a straight razor blade jury-rigged with the pointed end of a chopstick, threaded through the blade slits. I don't really have a special technique, the only thing I've tried to master is to slash bravely and quickly, at an angle (to the loaf), so that there's some overlap, “grigne.” Any hesitation in cutting, I find, drags the loaf, so I really do slash, rather than cut. Sorry for the vagueness – difficult to convey what I mean, but I hope it conveys something meaningful.
Edit: Oh, I should add, that typically a do a very long ferment, with often two or even three cold-ferment stages, including in the form, in cloth – so there's a bit of a “rind” by the time I get to bake day. That, too, helps the slash, I'm sure.