I'm curious about the submission throttling that you have experienced. You have 4 submissions from the last month (last 30 days) and 9 submissions for the two previous months. What is being throttled?

I don't know, but I rarely can submit new stuff...

When I joined HN I submitted a lot, but suddenly I could not submit for two weeks, then sometimes I can submit twice or three times in a week, and then have to wait two weeks again...