What is considered appropiate on FR is explicitly published by Jim Robinson, near the end of the FR home page. This list does not include righteously symmetric pinging behavior.
As a frequent recipient of the under-the-radar approach to argumentation, I would many times have appreciated it if it were on the list, but it ain't, and it oughten't--it's a silly restriction on freewheeling public discussion that pretty much only a kindergarten teach who has come to see fairness as the be-all of existence, or an annoyingly prissy spinster librarian would appreciate the value of.
Spot on again Don.