Many of us have asked for this, but multi-camera users are still a relatively small proportion of total users so it hasn’t been a high priority, but I’m keeping my fingers crossed that it will be implemented one day.
In the meantime, I find that if I use a small dither with the CCD on my main scope, I don’t see it in my piggy-backed DSLR because of the difference in image scale, particularly if you are using the DSLR data for lower resolution color only.
…Keith