This issue has been observed for as long as we have had error scans, and while it’s not exclusive to NEC burners, they do seem to do it more than others. What, exactly, it represents in terms of the actual burn process is pure speculation. We do know that it is speed-related, and lowering burn speed can eliminate it. When a drive pauses for re-cal or speed shift, it leaves a little “blank” spot in the groove, the length of which needs to be within spec. My hunch is that this is where the issue lies.
As to how it may or may not affect playback, the general idea is that it does not. That’s not to say that some of the picky drives might not stumble at this spot. Errors are errors, but the fact that one scanning drive reports errors at that spot does not mean that all drives will also have errors there. Even if they do, it may not affect playback. So, the bottom line is that it really depends on the playback drive, but the errors are real (in the scanning drive). Another factor, and completely random, is where this little blip occurs in the data stream.