Red_green,
That is great advice. I definitely fall into that "lazy" category. By weighted nymph do you mean a BH nymph? And when you do put split shot on what's the closest you put it on in regards to the fly? Is it with or without an indicator?
Come out to PA for five days in May and we'll go to my cabin on a famous wild trout stream and I will mentor you. You can pick my brain for five days and go home with a heck of a lot more knowledge about trout than when you arrived.
Actually by "weighted" I meant lead wire on the hook shank before tying the flies. But since it is not always easy to find nymphs tied in that fashion you can use BH nymphs. I've never done a study of whether the BH is any better than a plain nymph. But I bet it is easily as good. Just like guys are tying "hot spots" on nymphs now to get more attention from the trout beads glitter a little and look just different enough from the thousands of nymphs in the drift that a trout may perhaps single it out and eat it. Every little bit helps.
The "when to put split shot on" is difficult to answer. If your unweighted nymph is not getting down to the bottom and you are pretty sure there is no mayfly emergence underway where nymphs might be throughout the water column then that is when I might put on a split shot.
I never use an indicator when nymphing for non-migratory trout because I'm old enough to have learned to nymph effectively without a bobber. However when I fish for steelhead and nymph or bead I always use an indicator. Not so much to signal a strike but to minimize getting snagged on the shale bottoms of the streams I fish in PA and OH.
Sometimes it is much easier to get a drag free drift without an indicator. When you use an indicator you should always be seeing how it is floating and be prepared to mend it up, or down, stream to slow it down if it is dragging.
The rule of thumb for indicator placement is typically 1.5 times the depth of the moving water. So if the water is 3' deep place the indicator 4.5' from the point fly. That being said if you are fishing a dead slow pool with little current you probably shouldn't place the indicator any higher than the water is deep so you don't get snagged.