Imagine if you will:
- The L replaces #24
- When L is in the 5 spot, they get a side out and are to rotate
- #13 is in the 2 spot, and will be rotating to 1
- The L wants to serve in that spot in the rotation
They could execute this little maneuver using "longhand" -- #24 replaces L who comes off the court; L then replaces #13 who leaves the court.
Instead, they do it "shorthand" -- #24 returns to the court, #13 leaves the court, L does the quickstep to 1 to serve
Either way, it is exactly the same result: two libero replacements in the same dead ball. Bob was spot on in how the libero tracker records it, and in how the scorekeeper doesn't.