River muskies are not as sensitive to the "bite window" idea, or to atmospheric conditions, as still water (lake) muskies are.
With a river, if you're drifting it, you're unlikely to be able to pick where you'll be at a specific time anyway...you're going to be where you're going to be.
If the "hot spot" is in the first hour of an 8 hour drift, but the "window" is from 4:00 - 6:00...you're simply not going to be able to be there.
All that said, I agree 1,000% with the idea that the more time you spend out there, the better you'll get at it. With rivers, recognizing and setting up for the the important stretches is the key to getting muskies attention.
They'll still screw with you, and mess with your head, because they're Muckin' Fuskies. ?