Of course, optionally, {HEAD ~ non commercial or fewer repetition zero clearance cutting operations} also may be provided by {TAIL ~ the invention} 
provided by
Of course , optionally , { HEAD ~ non commercial or fewer repetition zero clearance cutting operations } also may be provided by { TAIL ~ the invention }
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL