I don't know if I'd do deads 3x a week. They're a really demanding exercise using a TON of large muscles. With that said, I do think that there's a benefit to doing a thickness day and a width day hitting back 2x a week. In fact, if I get in another back session in a couple of days, I will be doing a high volume width day. My plan is to alternate between 531 days and volume days. So far it has been just 531 because I haven't been getting in as often as I'd like to, but this week seems to be going better. Just need to get to sleep at a better time tonight and I'll hit 531 arms tomorrow. Pre-exhaust chest and back width on Friday and a volume leg day on Saturday. Then 531 will commence on Tuesday.