We have always gone to TX at the start of the season and the birds always seem not quite ready to cooperate in terms of wanting to come to a call. Our experience has always been that the birds are bunched up in large groups and tend to stay together. Of course, you can still kill gobblers under those conditions, but it is often by patterning and ambushing rather than your classic "call-'em-in" hunting.
Having spoken to a number of people that have hunted later in the season, they seem to think it is better to hunt later when the large groups have broken up and the gobblers are more willing to explore calling they hear in the distance. Either way, if you are on a property that has plenty of birds, you will most likely be able to figure out a way to kill them.