so are you going to go around the whole lake bed "laying it down" ?
You don't need to lay it down around "the whole lake bed" , just the last few feet. Easily done if you're placing your rigs by hand. You can also pin things down using backleads, disguise things better by kicking silt over your tubing/leader/lead.
Casting is obviously a different situation.
I personally don't use tubing, its too stiff and doesnt "lay" itself down very well on anything that isn't a flat bottom. It is a lot more effective if cut into shorter lengths to help it through the ups and downs of the lakebed (you can also alternate colours if you feel you want to break up the "single colour line" of the tubing).
A supple leader aided by either infused tungsten or blobs of tungsten putty is a better solution I believe.
Where any weed or "chod" as its often called then just about any sort of stiff or inflexible tubing or leader is going to end up draped over weed at some distance above the lake bed according to the height of the weed.
Its often better to fish with no leader or tubing whatsoever and slack lines to allow the line to sink as well as it can onto the lakebed.
, no no no, you have to use tubing. Never did tell me why.