I've said this before, but when I bought my current bike, the LBS owner tried to switch me from 165s to 170s. I said OK, I would try the 170s. Within one ride, I knew I hated them. I felt like I was struggling to turn the cranks and pushing much harder than I ever did, no matter what gear I was in (the bikes had the same gearing). In theory, the LBS owner said the longer cranks would "unleash the power he knew I had in me," which I suspect was just a crock. I am a spinner; I always have been. I didn't start out trying to be this way, or train any special way, but it's what I feel comfortable with. In fact, I can barely stand on the bike and only do very rarely.
On a group ride a couple of weeks ago someone asked me how I trained to get such a high cadence. I replied that it's just the natural way I ride (and I don't think an average cadence of 80-85) is that high.