The Celestron and Crayford focusers work in totally different ways. The Crayford works by having a small shaft against the side of the focuser tube so one rotation moves the focus by the circumference of the focuser shaft. Fo4 a 4mm diameter shaft about 12.5mm.
The Celestron focuser shaft is a fine pitch screw thread and one rotation moves the primary mirror by the thread pitch. This www.cloudynights.com/topic/645522-celest...ct-and-edgehd/page-8 says the pitch is 0.75 mm so 0.75 mm travel per rotation. At 1000 steps per rotation 0.75 microns per step. Even running the SCT in hyperstar mode at F/2 the CFZ is 10 microns so no problem. Maybe someone at Celestron thought about this.

The Agena Astro article is talking about mounting thread pitches, nothing to do with the focuser internally.

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