To add a whole pound is a bit high of an esimate.... using 6 fl-oz of CA on a plane would only yeild 1 1/2 to 2 oz of weight. When the CA cooks off much of its weight evaporates. Anything that needs that much glue is large enough that the weight gain is negligible in the finished airframe.

I 100% agree with using whatever it takes to make a good joint. The major thing is making tight fitting joints and you will use less glue; no matter what type. I use thin on tight joints and only go back with medium and accellerator if it needs a structural fillet... I use thick only when I need the added working time.