Tom,
I moved this post to this message board, since you ask a question about the workings of replies to posts on the forum.
To answer your question as to why one might answer their own post, quite simple really. A forum member saw my request for information and replied off-forum (in this case using the Private Message facility.) Had it been a public communication, or something they wished all to see, they would have post a conventional reply in this thread. They wanted to return a favor, without making a public deal about it.
My reply is just to notify those who might read the thread that I did indeed get a copy of the article which I sought; request fulfilled. That is the reply. And a bit of a plug that was via the help of the Douglas community here on the forum. Otherwise it would appear as if no one had yet responded.
Similar to if you have an item listed in the 'For Sale' or 'Wanted' section. When the purpose of the advert is fulfilled, one should go back an post a reply that the item is sold/acquired, if needed to clarify the situation.
All in the capacity of an ordinary forum member.
Also posting a reply flags the message as 'new', giving a visual cue to members that a reply or new information has been added. Editing an existing post does not flag a message in this manner, though if you happen to read the message, you will see a footnote at the bottom of the message to that effect of by who and when the last edit was done.
In moving your post here, and replying to your query, I am acting in a moderator's capacity. The only connection your post had to mine was that it prompted your question. I could not answer that question there without veering off-thread; which is something else one should avoid, though it can be hard! To answer it in terms of how the forum works, as you requested, places it solidly in this message board. And I hope I did answer it above.
If in future you have questions related to the forum or replies in general, please post them here. Separate them out from replies specific to the topics in other threads. It will make it a lot easier for us moderators to respond. This also may remove the confusion over some of us that have duel roles of ordinary members and as moderators, and when we are acting in either capacity. Also when carrying out a moderator role, I try to remember to sign off as such (see below.)
-Doug
Site moderator
This thread was split off from the following message after post #2-
https://www.douglasmotorcycles.net/index.php/topic,2575.0.html