Why not? I do.

I have 8 direct reports and I review every single line of code that they write. Some days this is all I do.

Others think I'm crazy but our group outperforms every other group by any measure. I'm convinced it's because of peer review.

A few thoughts:

1. Regarding resources and timelines: It's not when you start, it's when you finish. Every hour of peer review saves me at least 10 hours on the back end (systems testing, regression testing, user acceptance testing) and 100 hours on the back/back end (maintenance).

2. I never have to tell anyone anything more than once. I make sure I explain why. (When you do <x>, you cause <y>.) Then they learn and remember. This is not a religious debate; it's a way of conducting business. This won't work nearly as well if people are more interested in showing what they know than learning how to do it properly.

3. As I get to know different people, I know where I can skim and where I have to focus. I rarely return much to senior people. I often return a lot to junior people.

4. Everyone makes mistakes, even senior people, and even me. Peer review, like regression testing, is a pain in the ass, but it more than pays for itself on the back end.

5. As soon as you feel you're ready, you're senior people can take some of the peer review workload. I have done this before, but it hasn't lasted because of turnover.

6. Once people know everything will be peer reviewed, they become more careful about what they're doing.

7. Technical debt is a huge timebomb. I know of no better way of slowing it down than 100% peer review.

8. Everything is documented in the ticket. This provides some feedback on how it's working and what should be changed (programming standards, peer review methods, etc.)

9. Once you put your phone away, get off the internet, and stop going to useless meetings, it's amazing how much more time you have to do things that really make a difference, like peer review.

10. I hate doing this. I'd rather just code. But the only thing I hate more than peer review is fixing bugs. That's why I do this.