There are multiple good reasons for offering the optional position for U3 when rotated. It was discussed originally so that U3 would be closer to the point of the base and therefore easier to use the wedge mechanic when R1 is probably going to steal. Other advantages have developed from this:
• It will be easier to get into a position to see the force play. From the 3b side of 2b, U3’s initial movement can now be toward where the ball is hit to get the good angle to the throw being caught. This is true for a bunt or a ground ball. If the ball is hit toward the circle or left side of the infield, move to the right; and if hit to the right side, move to the left.
• The position also allows U3 to better cover 3B is the plate umpire is busy with ball status on a bunt.
• If U3 suspects the pitcher is violating the pitcher’s lane rule, U3 can move to the most appropriate position to get a clear view of this.
The optional position also has some minuses, such as covering both 1B and 2B to push U1 to the plate on a rotation. U3 will still need to read, adjust and communicate as the play develops. Use of the optional position may change depending on R1, the count and number of outs.
Umpires should continue to use the optional position and learn its advantages and disadvantages.