Upon detection of a first of the fiducial marks, the advance of {HEAD ~ the side edge} of {TAIL ~ the sheet} associated with the detected fiducial mark is repeatedly dithered rearward and then forward while the opposite side edge of the sheet continues to advance 
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Upon detection of a first of the fiducial marks , the advance of { HEAD ~ the side edge } of { TAIL ~ the sheet } associated with the detected fiducial mark is repeatedly dithered rearward and then forward while the opposite side edge of the sheet continues to advance
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH