It dosen't aid the defense any more than it aids the offense.

When I was a coach (long time ago) I always told my players to run to 1B on a dropped 3rd strike, hoping the catcher would forget and throw the ball into RF. It worked sometimes too. The mechanic I use does not always prevent this, because sometimes they don't hear in all the excitement, but it minimizes the times it does. Consider a similar issue, dropped 3rd strike on a pitch that may have been swung at but I (PU) did not think so. The mechanic I learned was go to partner immediately "did he go", don't wait for defense to ask, so the offensive player is not left at a disadvantage when the checked swing appeal is made, after the catcher comes back with the ball.