There are many different parts of the turkey season. They all vary across the USA as well as Central America.
If you are chasing Goulds, Merriam's’, Rio's, or Eastern turkeys we have all asked ourselves this question before our initial set up for the hunt. You have to consider how far along the breeding season has advanced. I can honestly say I do not think there is ever a time a lone hen decoy isn't an option. The big Tom's that you are after didn't get big by being dumb. They aren't just going to walk in to a blind set up where they hear a hen yelping. However if you are set up inside a timber edge hunting the field in front of you there is the possibility of getting by with no decoy at all. Your “hen” just has to sound real from the yelps and purrs to the actual sound of a turkey feeding and scratching through the leaves this can be accomplished by simply raking your hands through the leaves. Think back to last fall when you were sitting in the deer stand with turkeys feeding all around you what; did their timber talk and movements sound like this is maybe the only way you can call in a big gobbler without a decoy.
As for relating to what point in the breeding season it is, or even just the hunting season. Have you set up in the same basic area the last 2 weeks with the same basic triangle of love? - Two hens and a Jake in just about the same area and position? If so change it up. Being consistent is good playing baseball when you’re on the mound or in the batter's box. But if the birds you have been calling to, have seen the same old thing over and over they may be getting wise of that. after they stop gobbling an hour later “Bigfoot” is going to walk out and just pick up the “turkeys and stuff them into his vest/bag. They are still watching you keep that in mind is almost scary to think about a turkey CIA? Try a new set up one or two hens maybe a different Jake, maybe a full strut Jake decoy? Just change it.
If it is really late in the season and the hen are actively nesting and the toms are showing the wear and tear of fighting leave the Jake at home. Regardless of how big and strong any old tom is there has been a moment in his life where he got his butt kicked by a gang or single young bird and that will stay in his mind until your load of shot erases that memory. If it is early in the season set up your Jake and hen in a breeding position this will push the dominate tom over the edge. Who wants the 15 year old sniffing around the college girls and actually picking one up? None of us and it's the same with the turkeys.
Always if possible set your decoys in a highly visible area. You don't want that thick bearded bird to hang up 100 yards out just because he can't see that pretty little lady that's talking to him. He probably will take a peak turn around and walk off without another gobble coming from his mouth. If you have pressured the birds all month- like I have take out a single decoy grab a new call and hit the woods. a change in the visible attraction and the audible attraction is maybe the key to unlocking the trigger on your gun that has been quiet since opening day. Well I hope in some way this helps you I wish I would have thought it out better a week or two ago, tomorrow is that heart breaking last day here in Oklahoma and I’m still two birds shy of my limit. But with having thought out the past month I know how my set up and call bag will look in the morning. New slate/box/mouth call purchase is likely sometime today. Good luck and May god guide your bullets and arrows making them fly true.