Congratulations to you and your son on his first gobbler. I wish I'd started that early.
I have only used a full fan strutter one time when going after a dominant gobbler. A rainy night allowed me to get up under his roost quietly and set that strutter in his wheelhouse. He couldn't stand the intrusion and savagely attacked the decoy. The gobbler's impact was so hard that he broke the plastic decoy stake in half and knocked the fan 15 feet from where the decoy had been when he hit. It was pretty spectacular. He left two spur holes in my strutter about the diameter of an ink pen. I busted him with a load of Hevi #6s at 16 yards. He was; 23lbs. 8 oz., 10.25 inch beard and 1.25 inch spurs.
I loaned my strutter to a buddy who had one gobbler come close, then shied away from it. Another buddy of mine suggested making a jake fan and using a stubby beard like he does in his strutter. Gobblers regularly attack his decoy with no fear or shyness. Make your strutter decoy look like a bold, young punk Jake and mature gobblers won't think twice about coming in to thump him. Good luck & have fun.
Jim