ORIGINAL: KenWh
I had always been led to believe that the programming had to match, so that when the trainer switch is pulled, the controls don't go crazy. I didn't guess that it would prevent any function whatsoever.
In most other radios this is not true because most buddy boxes are not programmable. The buddy box only supplies stick input any special mixes, dual rates ect.. are done in the Master only. You only have to assure servo direction and trim switch settings.
It appears that Spektrum radios do it differently. A strike against them.