How to Avoid Large Holes in Crumb

I've heard those big holes called "the tunnel where the baker sleeps" or something similar.  How are you shaping this dough?  Do you divide it, give it a rough pre-shape, let it sit, then a final shaping?  A two-stage shaping can really help, esp w/very wet doughs.  Don't be afraid to degas a bit more than you are presently doing when you initially divide it.  Use a sharp knife to rupture crazy-big bubbles....when you shape (both times), concentrate on building internal structure in the loaf....stretch and fold over on a N/S/E/W pattern...really give the dough a good quick pull & fold, going around the points of the compass.  You are trying to preserve gas in the loaf, but to distribute it more evenly thru the whole dough mass.