Let Business Priority Drive You

Your organization has skills and areas of knowledge. Each person (or group) is good at something. You might take this to mean that the best strategy would be to give them something to work on that matches that expertise. That seems most efficient. Give them something they're good at and they'll get the most done, right? It depends on how you define efficiency. If it's how much they output per unit of time, maybe so. If it's how much business value they output per unit of time, maybe not.

Backlogs are a great thing. They force the organization to agree on priorities. What would produce the most business value given the amount of effort it would take to accomplish? That's the highest priority. Etc. Insisting things be ranked rather than put in buckets forces the organization to make decisions and just as importantly to have the discussions necessary to make those decisions. Lots of good things can come of that process.

Going back to people doing things outside their areas of strength... It might turn out that none of the highest priorities requires that expertise. In that case, you're likely going to be better off having that person or team work less efficiently (in the classic sense) on a higher priority item than they would have otherwise. This will not only allow you to produce more business value, but it puts the organization in a better position strategically as that person or team now has more expertise and flexibility. This allows you to more easily match priorities in the future. Over time taking this approach helps your expertise evolve to match the allocations that you need. If you keep people on the items they're best at, your skillset mismatches will remain unresolved.

Looking from a team point of view, the same logic applies. This is one reason that you want to go to as few backlogs as possible (see this previous post). It forces you to evolve your teams' focus to the business problems at hand.