Yeah, upper yellow (above yellow creek lake) and some of those tribs were pretty sweet. Don't get me wrong, there's a few good ones in the area. But keep in mind, even Berks County, in suburban Philly, has 50ish wild trout streams, and some of the "good" trout counties in PA have literally hundreds.
No, I haven't done much fishing down towards Robinson, but you're really getting into the Laurel Highlands there, I'd expect things would get better. I have lived in or fished NW, NC, central, and SE PA quite a bit, and made a handful of trips to the SC area too. But the Laurel Highlands and the Pocono's remain pretty large holes in my PA wild trout fishing resume.
Been a while since I fished Gilhouser. I generally accessed it from I think it was a game lands parking lot or something of that nature, not really sure. It was a little turnaround at the end of a road, there was a maze of paths through some thick stuff to get to the stream that were easy to get turned around in. Lookin at google maps, might have been Michael's Road? We fished both up and down from there. I do remember that in dry summers, the stream was intermittent in places in the upper end, so there must have been some underground flow. It got a little bigger, and worse fishing, as you went down into the more mature forest areas.
I hold that it was fairly open compared to most small brookie streams I fish. It may have changed some, but I doubt that much unless new logging or something took place. Yeah, there was some laurel. But laurel is nothing compared to mature rhodo!
Perhaps difference in the streams we fish dictates our differences in choices of tackle? I think that happens often on this board. Someone asks about tackle choices for "small streams", and one person answers picturing tiny, thick, high gradient streams in X area, and another answers picturing medium sized, lower gradient, more open streams in Y area. Then those two argue. But they're both right for the streams they fish, they just have a different base of comparison.
FWIW, many of the streams I fish rarely give you a chance at a backcast. Often its bow and arrow, if for no other reason than to get line in front of you so you can roll cast to get the extra distance. I also often do a shortened hybrid between a roll and a backcast, you kind of lift all of the line off the water like a backcast but don't throw it behind you, only bring it to your side before the forward stroke. If it's open above, you can also do up and down casts, just throw the backcast straight up!
The hard part is drying flies. Use floatant, when it begins to sink, bring it in and blow on it. When all else fails, change the fly.