I don't think you can rank IT developers on a single bell curve the same way you could an assembly line operator. It's more like ranking actors or chefs, where someone with an award winning performance in one role can totally flop when cast in a different role. So, which developer is the best fit relative to other developers depends on the context of the job. For example, some developers can code very fast and hold up well under pressure, while other developers are detail oriented. Some developers are part system engineer, while other developers are part business analyst. Some developers you want leading the team on a new project, while other developers are a one man show.