Pardon my suggestion, but it seems like this could solve the issue. Basically not considering deltaRA and deltaDEC if that part of guiding is disabled:

if ((!Options::rAGuideEnabled() || fabs(driftRA) < 1) && (!Options::dECGuideEnabled() || fabs(driftDEC) < 1))

There might be other code paths related to manual dithering that I did not check. Also feel free to ignore as I am not super familiar with the codebase haha.

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