2 RAIL or 2R I just left a discussion that was meant to be about 2 rail track radius (as opposed to 3 rail track) which is described by DIAMETER like O72. The problem is, many forumites enter discussions from the sidebar to the right of the topic, and the discussion was soon taken over by posts about 3 rail track, even though prior posts were about track RADIUS.
The simple solution to this is to type 2R or 2 RAIL as the first characters in your title (if you are starting the topic) and the Body of your post. Then everyone should be aware of the forum they are posting in.
Hopefully
Simon