Code management and your release process are right when they are unobtrusive. It should be easy and fast to get the source you need. It should be easy and fast to save your changes. The code manager should detect conflicts, and resolving them should be straightforward. There should be no waiting—if a pair needs to edit something, they should feel free to go ahead.
A good Extreme pair saves code very frequently, many times per day. If the code manager is making you want to release less often, fix the code manager. Rapid progress depends on rapid and frequent release.