Well, some clouds rolled in so I did some A/B testing. Looks like the delay code is indeed causing Slew to Target inaccuracies.

Due to fear of uncontrollable axis spinning, I went back to the hand controller PC Direct mode. If I comment out the delay code, I get consistently high "Slew to Target" accuracy. Tested with a few objects all over the sky, I usually get under 20" accuracy with the second image capture. I then un-commented the delay code. My accuracy now would always fall somewhere between 50" and 30", and never below 20". I then commented out the code again, and yup, my accuracy went back up.

I also noticed that my internal guiding error has doubled. I normally get 0.8" RMS. With the delay code, I'm reading the upper 1' and sometimes even 2.5' errors. Admittedly this is a different night. But my RMS has been stable for quite some time now and seeing it at 2' is definitely strange.

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