A locked state managed by the blocker greatly reduces {TAIL ~ corner cases} and simplifies solutions in {HEAD ~ the few remaining corner cases} 
A locked state managed by the blocker greatly reduces { TAIL ~ corner cases } and simplifies solutions in { HEAD ~ the few remaining corner cases }
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD