This allows {HEAD ~ the level shifter} to be designed for optimal transitional performance without the sacrifice of a potentially long propagation delay on {TAIL ~ the output nodes} 
This allows { HEAD ~ the level shifter } to be designed for optimal transitional performance without the sacrifice of a potentially long propagation delay on { TAIL ~ the output nodes }
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL