MHanes,
I'm not saying I wouldn't cast into said pool. I'm saying I'd give it my shot, but not get too downtrodden if it doesn't work out, nor would I spend a whole lot of time there if the situation isn't good. That's life. On a stream like VC, in a given day you may fish 40 or 50 pools. All of them have fish in them. Only a few of them are gonna be ideal under those conditions. Cover water, don't get caught up on a spot destined for failure, instead aim at getting to more of the spots which are do-able.
From a more broad perspective, like everyone else I don't have tons of time to fish. When I get my chance, I go, regardless of conditions. Nonetheless, it's important to have a lot of options regarding which streams, which stream sections, etc. And absolutely, I choose which one to go to based on conditions.
So, ok, I have a Saturday to fish. Had it circled on my calendar for a month. Come Friday evening, I realize it hasn't rained in 2 weeks, and the gauges say everything is low and clear. That sucks. But oh well, I'm still gonna fish. I'm just gonna choose a stream that's more likely to produce in said conditions. VC doesn't fit that description, so left to my own devices, VC probably isn't where I'm going in the morning. Instead I might fish big water, where spooking them is less of a concern. Or I might pick a really fast stream, where the pools are largely the same regardless of flow.
If we'd had gotten 2 inches of rain Friday night, I may choose Valley over those other streams, which would be blown out to the point they'd be very difficult to fish.
Conditions determine WHERE I go, not when.