An 11k karma is not average IMHO. You're way above average HN commentator.
I think that you just used the best tool for the job. That doesn't really mean anything about comments. You read what I consider low level comments and high level comments on technical and social subjects from the SAME nickname all the time at HN.
I don't know if that is true. I had an equally high comment number and I reset it. My feeling is that there are others that do that as well.
You can get upvotes any number of ways [1] putting out correct and admirable info is only one of them.
Likewise you can loose karma by simply mentioning a third rail issue or not fawning when the community (on a particular post) [2] is fawning.
[1] For example I tend to upvote the parent threads of my comments. That way my comment has a better chance of being seen is my theory. (Doesn't matter if I am correct since I am pointing out what I do and it's reasonable to think that others might do the same.)
[2] And this is important. You can say the same type of thing on one comment thread and be downvoted but be upvoted on another.