These guys are right on. Birds will work their way towards their roosting site during the early evening. The flocks I hunt tend to roost in the same place every evening.
It's a lot easier to go to a property you intend to hunt and listen for gobbling in the morning. Return late in the day and watch them roost from afar to where you heard gobbling that morning. This is especially productive when you're hunting an island of timber surrounded by food sources.
I've had success roosting birds in larger tracts of timber by watching a ridgeline at dusk. I think the birds like to be as high up as they can and prefer the elevation a ridge offers over the surrounding landscape. Glassing with good optics at dusk, especially before the trees bud, can be a great way to cover a lot of acres of timber and dial in a flock. I will say that birds in larger tracts are harder to pattern...they will use more roosting areas.