I have a hard time figuring it out myself. I try and add a post in order unless it has drifted from what the original poster was talking about. In that case I go to the top and post. Like you I get confused and don't want to hurt anybodies feeling over a post. Most of the posts on this board are over my head.Since I don't have much to add technically I usually stick to areas I think I know a little about. Unless someone is just asking for an opinion. Those I have However, informed opinions I run short of.