Jon Elson fired this volley in
:

You really want to make sure these scales are DESIGNED for CNC motion
CONTROL applications, and not just DRO or static position reading use.
I just went through a mess with a CUI capacitive encoder that looked
great, but I couldn't tune the servo loop well. I finally discovered
there was a really nasty LAG in the encoder's response to
acceleration.

They guarantee these for output up to 2MHz (10m/s on the 5u scales, or
2m/s on the 1u ones). There doesn't appear to be any processing other
than signal conditioning going on in the reader heads.

Besides... I can do all this at NO risk. I have the DRO, I have encoders
on my motors, and I won't be destroying any of it to have a go at this
method. All I'd lose initially would be my time to try it, and the use
of the DRO display, but I'd gain that back with the EMC display.

LLoyd