so that the input to said feedback element is either the data input signal or a combination thereof with {HEAD ~ the output} of the feedback element, as determined by {TAIL ~ said control signal} 
so that the input to said feedback element is either the data input signal or a combination thereof with { HEAD ~ the output } of the feedback element , as determined by { TAIL ~ said control signal }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL