Yeah, it really depends on how high and colored the water is.
For what it's worth, contrary to what would seem to be logical, DARK colors show up best in brown water.
Also, the largest trout become piscavorous (fish eating), and lay off the bugs. They take large meals less often. And generally feed either at night or when the water is high and brown, when they are invisible to predators from above, and their prey washes into their zone and doesn't see them coming.
So yes, high and muddy brings the trophy hunters out, for good reason. Black streamers are favored by many, including me.
But there are exceptions. For instance, mid-summer on more urban streams. Runoff is heavy and warm after running over all that hot concrete into storm drains. Water temps spike with the water, fish shut off. Wait for falling water, and cooling water temps, before fishing (but hit it before it's too low again), and the fish will turn on with the improving trend.
And in heavy hatch situations, I've seen fish rise enthusiastically even in high water. There can really be heavy flow and some color, but usually not "chocolate milk" situations. These are some of the best dry fly situations you can get, heavy current and low visibility means fish don't get long to inspect a fly, and poor imitations or slight drag issues don't hurt you so bad. Also, in heavier flows, bugs get washed around and drowned chaotically, much like your fly. The fish aren't so picky about emerger vs. dun (i.e. under the surface, in the film, vs. on top). They also concentrate into eddies and such more, so more fish in a smaller area.
