On USENET, especially without a threaded client, top-posting was a sin because it often removed valuable context - or forced the reader to scroll down to see the context then back up to see the reply. It also made for poor arguments in long threads where a poster would address multiple points at once rather than inline, point-by-point.
Similarly, when using non-threaded email clients the same problem exists. The bottom of the post becomes a mishmash of quotes and arrows (ah, "> > > > > > > > > > >", how we miss you) and almost impossible to figure out what the original poster was trying to say.
With threading, and especially Gmail's aggregate view of threads, top posting is far less of an issue. If everyone is using Gmail (e.g. Apps set up within a company), there's very little reason to reply inline for shorter messages, and more reason (phone consumption) to top-post. For longer discussions, though, it still helps to address points individually inline rather than attempt to pull them out on top.
Even within an organisation entirely using Gmail, there are still people who are sticklers for bottom-posting and seethe when they see top-posting. I used to be one of those people on USENET, but for the reasons above, I've changed my stance considerably.
Similarly, when using non-threaded email clients the same problem exists. The bottom of the post becomes a mishmash of quotes and arrows (ah, "> > > > > > > > > > >", how we miss you) and almost impossible to figure out what the original poster was trying to say.
With threading, and especially Gmail's aggregate view of threads, top posting is far less of an issue. If everyone is using Gmail (e.g. Apps set up within a company), there's very little reason to reply inline for shorter messages, and more reason (phone consumption) to top-post. For longer discussions, though, it still helps to address points individually inline rather than attempt to pull them out on top.
Even within an organisation entirely using Gmail, there are still people who are sticklers for bottom-posting and seethe when they see top-posting. I used to be one of those people on USENET, but for the reasons above, I've changed my stance considerably.