A grand piano sits on the baggage claim level of the Minneapolis airport. I’ve passed it more than 50 times in the past two years while riding the escalator up to departures, and I’ve seen it played three times. Once by a laughing young couple banging out a few chords together. Once by a lady expertly working the keys and pedals into concert music. And once, also beautifully, by a ground crew worker in jumpsuit and kneepads. This is the nature of a fractional view: seeing a group of people perform a specific task in a particular setting over a distinct time period AND recognizing the limits of the observation.
Asking who plays the piano is similar to asking who does what in an organization. Your analysis is bounded by how you define who, what, organization and the timing of the question. Which piano. Songs or notes. Roles or activities. How you define the fractions makes a difference.