There is a dark side to the separation of concerns. Lack of understanding. One person doing three jobs can fully understand what choices make the overal work more efficient. One DBA, one sysadmin and one dev only have direct insight into their own work. People, in my experience, can only optimize for what they understand and generally only care about their own work.

I believe this is why we are seeing roles, like devops becoming popular. Specialization introduces a communication overhead and most companies already do a terrible job of employee communication. Merging tightly coupled roles back together helps reduce friction and improve productivity.

In a small example such as your own, it probably works out closer to pipelining. The more common case, from my experience, is that the communication overhead and lack of understanding eat up more and more of your time as each new person is introduced. Law of diminishing returns takes effect and a year later everyone is always in meetings.