Wow, this blew up! Thanks everyone for your responses. For much of yesterday and all of today, Jamal was out with the hens and did great. I felt I should give him one more shot and so far, so good, but I have a dog crate ready in case he goes bad again. The hens finally stopped panicking and acting normal around him, and he wasn't interested in chasing them after that. My only concern is one of the pullets is super skinny and doesn't have an appetite like the others, and I was worried Jamal could crush her, but he's leaving her alone for the most part.
I have been VERY lucky so far that I haven't had any overmating problems. My first flock was two rooster and three hens (I was young, didn't know better) and even once the roosters started fighting, the hens weren't overmated. I have one pen right now that's just one roo and one hen, and she's in fantastic shape, I hardly ever see him mating her. Ideally I won't ever have roosters again -- once these all die out, I'm only planning to have hens. Of course, that's probably at least ten years down the road with how young Jamal is!
I've seen those tie outs, and I will keep that in mind if he acts up again.
Don't tell me that about the RIRs... Jamal's got that in him. His mother was said to be pure RIR but I believe she was likely a production red of some sort. I'm not sure.
I've learned though that chickens do not always fit their breed descriptions. Jamal's father was a Cochin bantam rooster. Everywhere I look, I see that Cochins are the friendliest chickens and the roosters are so sweet. That rooster was the meanest animal I've ever known, would literally almost kill himself attacking people, other chickens, dogs, wild animals, anything. I tried to tame him for three years and he never did settle down.
Jamal did spend his first almost four months in a flock with a rooster and three hens, but they were bantams, so by the time he had to be removed he was bigger than them. They used to chase him around and beat him up and I thought maybe he'd learned from that, but once he figured out he had outgrown them, it's like he never learned a thing.
He hasn't run at me or bitten me once since he got these girls, so fingers crossed it won't happen again.