Catcher Interference

[dddunn3d]

See NFHS, 8-3-1c.:

Each runner, other than the batter-runner (who is governed by 8-1-2) is awarded one base when:
c. he is attempting to steal or he is forced from the base he occupies by a batter-runner or runner who must advance because the catcher or any fielder obstructs the batter, such as stepping on or across home or pushing the batter to reach the pitch or touching the bat (8-1-1e). Instances may occur when the infraction may be ignored (8-1-1e).

Macaroo...

I would think that J/R means that if B1 removes himself from the batter's box in an effort to avoid hindering or interfering with the play, then he has given up his opportunity to swing or bunt at the pitch.