PoSR77,
What you're describing is posting back-to-back, where one of your posts follows another of your posts in the thread. This is something Head-Fi does not allow under our Posting Guidelines.
From the message you received: "Double posting replies goes against the posting guidelines." A double post is two or more in a row. From our Posting Guidelines:
You will need to use the site's multi-quote function if you'd like to reply to multiple people. Based on what you've stated about posting what you're listening to, you'll need to edit the previous post whenever you'd like to make a new post in a thread when you are the most recent poster. This is working as designed.
Edit: For an example, posting back-to-back (double posting) like this is not allowed under our Guidelines.
https://www.head-fi.org/threads/todays-ecm-playlist.971461/page-15#post-18537509
As for quoting people, that's not what I was doing. I'm just posting (some) of the same content
in two different posts in two different threads. Worked fine for years.
Here's an example:
1) 1st post in the "what are you listening to now thread". Notice the ECM album I posted in that "catch all" thread.
https://www.head-fi.org/threads/what-are-you-listening-to-right-now.253245/page-9748#post-18552635
2) Less than 5 minutes later, I posted the ECM content from the post above in the ECM thread.
https://www.head-fi.org/threads/todays-ecm-playlist.971461/post-18552644 As you can see, it's not spamming since I'm only posting some of the same relevant content already posted in the other thread. I'm not posting all the same content/albums over and over in thread after thread.
Also note that the above linked post in the ECM thread is right under an earlier post I had made in that same thread. So I was the last poster in that thread and yet able to post again before anyone else did. So a double post in that sense. Just as I've done for years.
And as others have pointed out, the "if you had the last post in a thread, you can't post another in that thread until someone else posts" is absurd as many threads are low-traffic and filled with one, or just a few, posters who now have to wait until someone else posts (which can be days) until they can post again, or endlessly edit their last post which will 1) crowd up that post needlessly, and 2) keep the thread not bumped or refreshed so others who see it or follow it won't be aware of new content added to it.
As long as a single person is not posting like 10 times per day one post after another in the same thread (spamming the thread) when no one else is posting, what's the big deal? My
ECM playlist thread is largely made up of me, or one or two others posting, sometimes days apart. So if I'm the last poster from a day, or a few days ago, and I want to post again, I can't. I have to edit my last post. Same with anyone else posting in there. That's just silly. It punishes less popular threads and rewards more popular ones. And that's unfair.