...you should use Joint Stereo if possible, is because it makes a more efficient use of the bits...

But only if the material is not 'very much stereo', i.e. the difference of channels is small compared to their sum, IIUC. That wouldn't be the case in Dixieland's example. That said, I never noticed problems with joint stereo encoding myself, even on albums by artists who occasionally use quite drastic stereo seperation (e.g. Tomita, Rick Wakeman, Walter/Wendy Carlos, Pink Floyd).

Dragi "Bonzi" Raos
Zagreb, Croatia
Q#5196, MkII#80000376, 18GB green