Aries @ The belly lam's are a good way to bring up the weight of a weaker bow that has a crowned back, also it will allmost "pre-tiller" a bow if you want to glue one up in a form right from the start. Ya can look at it sort of like making the lams form the belly taper of the bow limb.....and as long as ya have the long "feather-edges" on the lambs being on the compression side makes them pretty much not able to lift as they might do on the back or tension side. Also you can tweek the draw profile of the bow by what wood ya pick for the lam, how long you make it, and where on the bow you glue it up. One last thing is if you have a bow that has somewhat "flat" cast you could glue on a higher density wood (usually snappier) and gain some cast all the way through the power stroke.
Ever since Ken did that first one, I've done 4 and they seem to work very well, pretty neat actually.
rich