I tend to agree with most of the other posts. It is impossible to predict when birds will gobble. However, one of my favorite times to be in the woods is after a rain if the sky clears and the sun comes out. That is the one time I really expect to hear a gobble, and often do.
I worked at a state hospital for a few years after high school. It was a large campus, with huge mature oaks and a population of hundreds of squirrels, which, some days, would be running around everywhere, and others, you wouldn't see a one. I squirrel hunted a lot back then, and if I got off work in the afternoon, and didn't see any squirrels out, I wouldn't bother with going hunting because it was likely I wouldn't see many in my hunting woods either.
I've hunted turkeys long enough to believe there is a rhyme or reason to why they gobble or not, I'm just not sure us humans will ever fully understand that reason. Sure, where they are in the breeding cycle has a lot to do with gobbling activity overall, but like all of you, I've hunted a property one day, and heard birds in every direction. The next morning, nothing, and common sense tells me that not every bird gets to an identical situation in the breeding cycle in 24 hours.