I've tried everything with mine. For a while I thought I had stopped the aggression. It was only a pause. He went back to the random attacks but they're pretty much limited to 10%-15% of our encounters and more upsetting than painful.
I can't put him down. I did his father and I still hate myself for it so I can't do it again. What I do do to live with him is:
1) Keep long, strong sticks around the chicken yard in various places if I have to hold him off.
2) Keep a putter at the gate to the yard. If I am going in to do some business that's gonna take some time, I have the putter in my hand. It has a long reach and a heavy head down where he might threaten.
3) Use the putter to herd him into the enclosed run if I want to work in the yard and into the yard if I want to work in the run.
4) I've found that if I go directly at him he's gonna start raising his hackle feathers and prepare for an attack. If I approach him from behind or the side he's going to move along to avoid the putter.
5) If he attacks, I don't back down. I have to make the point that I'm going to best him every time.
6) Keep him in sight all the time but if I have to turn my back on him, I still point the putter in his direction and wave it behind me.
Most of all, I wouldn't go near him not wearing long pants. He's never gone at me higher than my knees.