BILL W: i sure don't pretend to have all or even most of the answers, but i can relate my 2002-2003 trouting experiences on banks lake.
in broad, general terms, most of the hookups i've had have been in approximately 25 feet of water, in water 50 degrees plus-or-minus a bit. north of the coulee city marina a little ways, along the face of the dam, and along the west wall. trolling in shallower water along the east side (north of coulee city) produced nothing for me.
here and there along the wall you will find wash-out areas that resulted in underwater alluvial fans. in other words, 20-25 or so feet of water bordered both to the north and to the south by deeper water. i've had some activity on top of the fans, but numerically more action either just north or just south of them, in the deeper "pockets," so to speak, very close to the shallower flats.
trolling depth: neither TROUTFISHERMAN nor i added any weight. i use spiderwire which has a diameter of 8# mono, and i don't know what strength of mono jim fishes with. but we both would have sworn that our lures weren't any deeper than maybe 3 feet, with 50 to 90 feet of line out. we WOULD have sworn to that, UNTIL we crossed a rocky mound that came up to within 6 or 7 feet of the surface, and we BOTH hung up on the up-slope of it!! talk about a surprise!
so . . . . . . since we snagged the up-slope, maybe our lures were at 8-9-10 feet. after that i've stayed closer to 50-60 feet of line out, since i WANT my attractor to be above the trout, reflecting down into the depths.
i hope this is of a little help to you, and perhaps jim will post a reply, giving you his views and also filling in gaps that i've left.
john