[nradov]

That's a management failure. The organization can't depend on a single developer being the only one to understand a module. What happens when that developer leaves, even temporarily? A competent manager will dedicate time to cross training so that at least one other team member understands everything, even if this causes a short-term productivity loss.

[maxxxxx]

That sounds good but in our case that's really not feasible. If a certain developer leaves almost anybody in the team can take over his work in a few weeks. But nobody has the team to stay up to date all the time. We would have to staff up quite a bit. This would be nice but it ain't gonna happen.