Day 5 PM: Firehole - Puzzling??

I went back to town after stream-side lunch. I had to do a load of laundry, meanwhile dropped by Blue Ribbon Flies, crossing the street, for shopping and fishing intel. Relaxing in my motel room and stuffing early dinner on purpose, I went to Muleshoe Bend of Firehole. A group of three anglers started to fish the bend right in front of me. But I knew they were not doing right and these kinds group fishers usually don't stay long. I fished a section below, actually a nice run, till they were gone.

White Miller was so visible as in the Madison in the morning.

It seemed to be an easy money to fish with White Miller X Caddis,

trailed with Nick's Caddis Soft-hackle.

I saw lots of bank feeders but they didn't even look up my flies, yet still kept on rising. I made sure that I was dead-drifting and swinging correctly, still no bites at all. A bit confused, I walked toward the bank to see what was floating. There were mass of tiny caddis on the water, emergers and cripples.

Adults were crawling on my wader.

I switched into smaller X Caddis and Iris Cadis in my box. That meant to be Glossosoma (size 20 with black body). I finally started to move trout. They started to pounce my flies but just looked skeptical.

At the end of the day, I caught a bit larger one of White Miller X Caddis while swinging.

But it was really puzzling. Trout were not interested in White Miller and smaller patterns wouldn't quite get it right............ What was going on??

Little did I know that I would learn more in the next two evenings.......