I'm in no way, a fish biologist, just a lowly fly fisherman! But, even though 'Cutts may or may not be "classed in different classes", I DO KNOW one thing for sure about them......... there's a vast difference, in fishing for and catching, say; Lake Dwelling Cutts and West Slope Cutts, not to mention the Sea Run Cutts.
The West Slopes are by far one of the wildest and most fun to fish for, for me anyway, when fished for in remote streams. The more, remote, the feistier and usually the more wary and hard to hook, they get. But,when that hook up is made, they're hell bent for leather to get to the net, if they're 6" or 16"! A "take on a dry" is a very exciting take, when done by a wild cutthroat, more so than any Rainbow I've ever hooked.
When netted, just looking at their coloring, especially if they're in pre-spawn colors, makes them one of the prettiest fresh water fish that swims.
The Sea Runs, the ones I get to fish for the most often, because I live at the coast is another Cutt that is very, very, exciting when it hits your dry fly offering! Unlike, the West Slope though, they seem to prefer the really garish, loud colored, flies as opposed to anything resembling the old "match the hatch" theory!
Bright pinks, mixed with reds and lime green, as awful as that combo sounds, makes for a fantastic, Sea Run dry OR wet fly. When they're fresh in from the salt, they're quite the fish to tangle with, on a 3 to 5 weight rod. Although, I wouldn't class them as a "technical fish" to fish for, like big Rainbow and Browns can be, they're still a wary adversary at any level.
You can get some really great Sea Run patterns from several web sites, featuring west coast fly fishing, or, from a book like our own fly club's published book "Northwest Fly Patterns and Tying Guide", by the "Rainland Flycasters" of Astoria, Oregon.