After I saw Tom, the product owner in action, the degree of commitment to the product and to the team by the product owner got a paradigm shift. He was indeed leading by example. He was going that extra mile to the details of the features of the complex product they were building as part of the user story grooming exercise with his team. As a product owner, I use to loose interest in the planning meetings as soon as the story points were estimated. After seeing Tom in action, I sat through two planning meetings with my team, till the user stories got decomposed into tasks, and the task estimates were done. Yes, I did not impose any of my views on the estimates. In fact I was answering the functional queries and helping the team to capture all the estimation data into a spread sheet. The result is amazing. At the end of the planning meeting, the tracking boards are ready.
As a product owner, one is an integral part of the team. What you get is directly proportional to what you give to the team.