No Calls?

[AtlUmpSteve]

Here's an area of relative inconsistency, unfortunately. Whike the credo of "no ball, no call" exists, most all the other plays you mention are expected to have, at least, an acknowledgement. I guess the point is that a no call means the runner is safe, while other situations create a change in count or circumstances, so they require at least some minimal acknowledgement.

So, for starters, all pitches deserve a call; every pitch that is not hit is either a ball or a strike, and deserves either a verbal call or signal. Since there is no signal for a ball, it must be verbal; even if the ball bounces to the plate, or hits the screen on the fly. Swinging strikes are not verbalized; but they are acknowledged by a signal, so that the defense knows that they don't need to ask you to check (in adult slow pitch, though, you may enjoy verbalizing!!). All outs require at least a basic out signal; obvious outs need not be verbalized. Obvious foul balls are the only category you mentioned where mechanics suggest no call or signal is considered necessary.