Along the north side of West 35th, West 36th, West 37th and West 38th Streets between Tenth and Eleventh Avenues, for zoning lots greater than 20,000 square feet, the City Planning Commission may authorize curb cuts, provided the Commission finds that such curb cuts are needed for required loading berths, do not unduly inhibit surface traffic or pedestrian flow and do not impair the essential character of the surrounding area. Loading berths shall be arranged so as to permit head-in and head-out truck movements to and from the zoning lot and thereby permit a more efficient loading operation.