A walk along the signal path clearly shows the eye at each location.  At Test Point A (TPA), a clean eye is clearly visible at the starting point.  The eye is gone at Test Point B (TPB) after the long cable run with high loss.  Test Point C (TPC) is after the EQ stage.  At this point the jitter is reduced (but some is still  present) and the amplitude has been recovered (re-driven).  By the time the signal reaches Test Point D (TPD), it has gone through a retiming stage, further reducing jitter, and a signal conditioning output where de-emphasis has been enabled and the signal is pre-distorted to counteract the expected loss that will be encountered in the next cable leg.  This results in the signal meeting the downstream device’s input requirement when the signal reaches the end of the cable at Test Point E (TPE).