That's what the trout have been saying the last couple of evenings. Anything less (larger), and we'll just take a quick looksee and not even move from our cushion on the stream bottom.
Even when the size was right, the drift had to be pretty darned good to elicit a rise and closeup inspection by the trout. Only a perfect presentation was worthy of a take, and most of those were done with the utmost caution. Nerves of steel were necessary to get a hook up, as the takes were so touchy - you had to wait a split second before tightening the line to set up. They needed time to actually sip it in, as the fish somehow knew that an artificial fly typically disappeared the second their lips touched the fly. So....you see the trout rise to the fly, he tips upwards and glides through the water column, eyes on the prize. Sometimes he turns away at the last moment, seeing something he doesn't quite like, leaving a soft wake that pushes the fly just enough to see it move. Other times, he opens slightly, hesitates, and if you can stand to hold your relaxed tension for one half second more, he sips it in...........barely. When the hook did find flesh, it wasn't much.
This little, size 24, blue-winged olive took a bunch of browns and rainbows the last couple of evenings. It got beat pretty bad, but is still fishable as you can see. And because I'm blind, I didn't notice I had forgtten to flatten the barb on this one and only noticed when I looked at this blow-up of the fly. Tsk, tsk..................
I also took a few on this simple midge emerger.
And finally, the Isonychia/Slate Drake emeger tied with a caribou hair wing. As dusk approached each evening, enough of the naturals started to hatch that I could switch to this larger fly (that I can see, damnit) and continue to catch fish. This is another well-chewed fly that will be fished until it falls apart or joins others in a tree branch.
Get out and fish. The weather's fine, and the fish are cooperative.