Hi Charlie: I've never fished Superior for steelhead, but before it got to be largely a take-a-number, "sorry about hooking your hat on the backcast" situation, I logged a couple thousand hours fishing for steelhead on the Lake Erie tribs in my native Erie County, PA.
Other than probably stream size differences (the Erie streams are quite small) and the high incidence of wild fish in the case of Superior (compared with their virtual absence in the Erie fishery) there are likely some similarities between the fisheries.
So, for waht it's worth, here are a few things I believe to be generally true of great lakes steelhead.
1) These are not particularly bright (as in intelligent) fish, but in higher pressure situations, they can get jaded. If you aren't having luck with the standard flies/fare, try something completely different that you're all but certain nobody else has tried there that day. This often will pay off with a take or two.
2) As these are traveling fish, when the run is well under way, virtually any current break is a possible worthwhile fishing location.
As Gonzo sort of suggests, you need not fish in the obvious biggger holding pools where the guys are all queued up. Check out that little half-bathtub size pocket with the single stick hanging in it along the bank. Often, there will be a fish there and he is likely to be more receptive to your offering not having spent the entire morning dodging wooly buggers, egg sucking leeches and sucker spawn. Look for the little pockets between the pools. So long as it is physically large enough to hold a fish (the size of a decent Samsonite suitcase laid flat) and deep enough (as little as 2 feet depending on water clarity) to "hide" him, it's worth fishing. I've had most of my best days picking pockets in this way. It can be nice and peaceful and about the only thing you miss out on is hearing where everybody else is from, which as sociable as I am, has never helped me catch a single fish anyway...:)
3) A general rule of thumb on water temps (at least in the Erie fishery) seems to be that these fish will chase a moving fly (streamers/buggers, etc.) so long as the water is 40F or above. Below that, you're better off dead drifting egg flies and the like. In my experience, this has been a pretty hard and fast rule, almost as if every fish carries a piece of paper that says this is how he must act.
It may be different up there, but I'd also add that it seems to also work this way on the WI Lake Michigan tribs like the Manitowoc, Sheboygan, etc. when I've been up there.
4) If you know there are fish in the river and you find a place where there "should" be a fish but are not getting any hookups, be persistent and change flies a couple times before you move on. This is related to these fish generally not being very bright as well as their occasional tendency to schizoid behavior. You never really know when they are going to wake up and decide they want to eat this thing that keeeps going by, but they want it to pass within 11/32nds of an inch of their nose and the best you've been able to do so far is 27/64ths. Lots of times "no sense makes the best sense" is the order of the day over these fish. They'll turn on and you won't know why and then they'll turn off like a light switch and you won't know why that is either.
5) On cold days, the last 90 minutes of daylight is worth the entire time between 8AM and Noon. On days when it is not so cold, both early and late are better than mid-day. On high blue, cold front days with a crisp north wind, except for the fact that nothing beats fishing, you might be better off taking guitar lessons or something. This, at least has been my experience.
One final thought: I've heard that on the North Shore streams, the water goes through the drainages like poop through a goose and that timing your trip to optimize the water levels you'll be fishing is very, very, impt. But I wouldn't suppose to know anything more about that other than to advise you to seek out local knowledge on how this affects things.
Best of luck,
Lee