Early morning when the toms are struting for hens I like a strut decoy like the pretty boy. I have had strutting toms just ignore the foam jake decoys and stay with the hen. Now when you put that strutting deke out and a henned up tom eyeballs that thing he will go beserk and walk right away from that hen to start a fight. They can't stand it.
After the hens have seperated from the toms later in the day, I either use the foam hen or no decoys. Where I hunt the toms are a little shy when by themselves and will hang up on the strutting deke and sometimes will bug out when they see the hen deke.
My experience has been that the only consistent decoy effect is the strutting deke on a henned up bird. I guess he can't look bad in front of the little lady.