Celestron has announced its new Focusing Motor for SCT's and RASA telescopes. Comes with ASCOM and native support. Relatively cheap in price at $199.95 USD. Available soon. Stay tuned.
This is great to see - and I didn't know about it until you posted the link. Here is a direct link to the celestron page:
I have my own stepper motor connected to the primary focusing knob and have been focusing this way with EdgeHD11, EdgeHD8, and C11 for many years - and it works very well despite its simplicity and low cost. I have posted focus curves and more recently temperature dependent plots showing how well it works and how reproducible it is - along with deep sky images with low fwhm.
It works very well with autofocusing routines as long as you include about 1/4 to 1/2 turn of the knob for backlash compensation - and focus by turning ccw. There is no need to apply mirror locks.
There is some confusion about the difference between f/10 focusing and f/2 (hyperstar). If you focus by moving the primary mirror then f/2 is no different from f/10. In fact, if the min fwhm you get is larger at f/2, in arc-seconds, then hyperstar is actually less critical than focusing at f/10. I have numerous examples at f/10, f/7, and f/2.
Finally - there have been exaggerated reports of temperature drift with SCT's and a need to refocus rapidly to track it. I have posted multiple studies of focus drift while imaging that show there is little need to focus more than about every 40 minutes - unless the scope is somehow far from equilibrium at the start.
So - this is a fortunate example where the simplest and lowest cost solution ends up also having many advantages - including no loss of backfocus - and a fully rigid and lightweight imaging train. Now that celestron offers a low cost focusing motor that attaches directly - it is even better.