For those that do it, there is a new calculation for the weight of salmonoids that will actually make your fish weigh more (and is more scientically accurate). The May Fly Fisherman mag reports a study in which the formula is changed to length (to fork of tail) X girth squared X divided by 690 (instead of 800). It adds 16% to the weight.
Another article, by Kelly Galloup, shows a number of interesting ways to set up your dropper rigs. Unfortunately, neither article is currently available on the web site. If their is an interest, I can draw similar rigs and scan the drawings.
Here's a freehand depiction of rigs. I didn't include the standard which most of us use. Blood or surgeons knots are used to control dropper loop movements, lengths of tippet for depth and droppers varied to control depth or reduce hook to hook tangles. Weight location controlled by B/S knots or double overhand when weight is terminal. Copy image and expand to make more legible.