Harlan, I was having one of those days on the Y, nothing working, was completing a drift below the Highway 20 bridge, and paused to look upstream to check if there was some other fishy-looking lie that I missed. That caused my two-fly rid to float up the surface (a worthy emerger imitation) but it held there for 10 seconds in the current (not worthy). Wham! Got hooked up...
The only thing I take away from that is that it's better to be lucky than good...or that trout really do have a pea-size brain.
Wild Bill