Hey SD,
As others have suggested, if you're looking for the most effective then go bounce/float some bait to 'em.
Flyfishing is a method that sacrifices some degree of effectiveness for esthetics. The most esthetically pleasing, to most steelhead flyfishers I know, is swinging unweighed flies on a floating line.
The entire continuum of weighed flies on a floating line/sinktips/nymphs or glo bugs under a bobber (or just leaving the fly rod in the car) are IMHO a concession to two factors, (1) the difficulty of the conditions we encounter and (2) your personal 'need' to catch a steelhead.
Let me explain. In the cold and often discolored waters of winter, steelhead typically won't move far to strike a fly or do so as aggressively as in spring/summer/fall. Therefore, your chances with a floating line and unweighed fly are almost Zero. You ~could~ do so, hoping to catching lightning in a bottle. And you'd have the company of famous flyfishermen like Bill McMillan (who still uses heavy wire hooks to "up" his odds a bit
).
Most, however, choose to use sinktips to deliver our flies more easily to the depth where these steelhead are holding. Some opt for weighted flies (with or without sinktips), and others resort to bobber and nymph (Steve Probasco is a well known proponent of this method). And some just leave the flyrod in the closet until spring.
You can choose however you'd like to fish 'cause NOBODY'S KEEPING SCORE!
If you enjoy fishing the bobber and nymph, then go for it! Ditto if you want to persist with the floating line and unweighed fly.
We'll each spend quite a few hours waiting for that next strike, so it's far better to find a method you enjoy and then strive to be as productive as you can be with it.
Or, to put it another way, you'd be a fool to be standing out there in the rain and wind hating casting that bobber and nymph as the lead whistles by your ear and hoping that it's going to give you an "edge" over your buddy swing speyflies in the tailout below you.
I saw a good sig the other day - "It's more important that you fish than how you fish"
Tight Lines whatever you decide to use!
Brian