{HEAD ~ The logical data volumes} typically have {TAIL ~ performance requirements} that cannot be met by a single storage array 
typically have
{ HEAD ~ The logical data volumes } typically have { TAIL ~ performance requirements } that can not be met by a single storage array
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH