I know this is a confusing issue, but just so we understand this 2.0 mono, and 1.0 mono areessentially the same thing just decoded differently. They are just listed carelessly. If we were listening to mono dialog from a 5.1 channel soundtrack all we would have to do is mix a discrete center channel only. Since we are talking prologic decoding, there is no discrete center channel. So information MUST be encoded equal level, and 0 degrees in phase into both the L and R discrete channels(much like Dolby stereo) in order for the decoder to derive a center channel signal. The 1.0 mono is essentially the same thing, except that the sound engineer used the discrete palate, and encoded the mono information in the center channel only WITHOUT dolby prologic decoding. So 2.0 mono is the same signal, mixed at the same volume, 0 in phase, and encoded into two channels to be decoded by prologic and directed to the center channel. 1.0 mono is the discrete version that uses only the center channel for the mono signal, and does not require any dolby prologic decoding to place the mono signal in the center channel.

Sir (head spinning in circles) Terrence