Cubase and 5.1 Panner question

I found that when mixing in Cubase 6/7 - I cannot pan a surround signal.
So If I already have a 5.1 mix of some sort, I route it to a 5.1 group track - I do get a surround or any kind of panner on the 5.1 audio or group track. I do get the 5.1 panner when sending a mono or stereo signal to a surround group, but I cannot pan a signal which already is surround. Why?
It does make sense that you cannot pan a Mono signal which is going to a mono group, but other than that there’s no reason not to be able to pan freely your surround signals.

I did notice that it is possible to do it in Nuendo, but not Cubase.
I’d like to see that option in Cubase, unless there’s a very important reason not to have it.



With a discrete 5.1 file the different channels are determined already anyway. And how should cubase know, which of the 6 channels you want to pan where with only one panner…? You´d need 6 panners in a one track to be able to pan all the 6 different channels.

That is correct. One panner point per audio channel.
This is possible in Nuendo today, but not in Cubase. The question is why?

I guess for Music production it’s not that big of a deal, but when mixing audio for film those possibilities do come in handy, and sometimes quite important.