Can't tell you what dive number, but it was probably 25-35 dives in No Cal. You start to feel very comfortable, no butterflies, and everything is second nature.
It probably has to do with where you dive. I would feel like a newbie cave diving, since I have never done it before, even with my hundreds of dives.
When I was in IDC in FL, I went on a casual dive with another instructor one day. We went to sign up for the boat and they said there were 3'-5' swells and only 15' of vis. The captain asked me where I was from and I said No Cal. He said, Oh, you will love it, LOL.
The other IDC candidate I was with was a FL native, and I could see that she was uncomfortable diving in those conditions, but she wanted to go. We went diving and she stayed right next to me, I navigated, and we got back to the anchor line about 35 min later. She said "how did you get us back here?" I am used to diving in conditions much worse than that, so navigation in poor vis is easy for me now. She was not good with it though because she had always dove in very good conditions and didn't use her compass and navigation skills much. Think about it, do you use a compass walking down the street when you can see for miles?
To make a long story longer, it has to do with the conditions you dive in and are used to.