How do you want the Panasonic during this. With center/no center?
With centre, please. This way you can tell whether the 950 disengages the centre even on bypass. (I have a friend whose pre-amp takes "analog bypass" very seriously; i.e., he can set centre to none, he can even unplug the unit, and the signal goes straight through to the output.)
Meanwhile I'll try to find a DVD-A disc that has exclusive centre channel content in order to test whether downmix is occuring.