Remeber, Jim Bush @ UCLA was Tellez' mentor early in his career and the 5-4-3 breakdowns were one of Bush's staple workouts.
Why do the 4-3-2? One could argue that Tellez felt it was very important to develop his athlete's glycolytic abilities, which would dovetail with the intensive nature of the 4-3-2 session.
Note: The SMTC crew could all produce world-class marks at 100 AND 200m fairly consistenly.
Food for thought.