I don't race anymore on a regular basis, in fact, I can't remember the last time I pinned on a number and tried to be first across the line. That doesn't mean I don't enjoy pushing myself or going fast, it just means that I don't race.
One reasonable question is how do I measure how I am performing? Of course, if you race, you can measure your performance on how well you did against your competitors. Obviously, that doesn't mean that you have to win to feel good about yourself. It just means that racing allows one to set some pretty specific goals like wanting to finish top-10. If you meet those goals, life's good.
If you don't race, what kinds of goals do you have? One of the goals I really don't like to see people set are those that are based on how they perform with respect to other riders with whom they ride. You know what I mean. Comments like 'as long as I beat Joe to the top of the climb, I feel good,' are pretty common. As I just said, I don't like those comments, especially if I am 'Joe.'
Frankly, I don't want anybody using me as a 'stalking horse' to judge their performance. This is one big reason that I have written here before about loathing the situation where I pass a rider and they decide to draft me without asking permission. I really don't know what is going through their mind. I think it is proper etiquette to ask permission to draft, but that another subject.
I think people who don't race should figure out a way to base their performance on something that doesn't involve how other riders are performing. So, you caught and passed a rider. Big deal. You don't know what that rider's agenda is. Maybe the rider is just finishing six hours in the mountains. Or the rider is getting over being horribly sick or injured. Or best yet, what if the rider doesn't care if you are catching him/her. Let's face it. It's only a race when you have a number on your back and somebody says 'Go!'.
A corollary of this whole situation are riders who show up at group rides and turn them into unofficial races because they need somebody chasing them to be able to push themselves on the bike. My friends who are pros train by themselves when it is time to go hard. They have internal motivation to push themselves as hard as they need to go. That's probably why they are pros and most of us are not.
I think power meters are a great solution to this problem. These tools don't lie. You are either going hard or you are not. I would suggest that non-racing cyclist who are looking to set goals for themselves to get a power meter and some knowledge, like a coach or a good book, on how to use the power meter to measure your performance. This really is the only way to truly measure your performance.