Yeah similarly we can make a few distinctions here:
1) Intended signal, true
2) Unintended signal, but true
3) Unintended signal, but false
(Sure, 1' intended but false; though not really important here)
replyWhen (1) obtains we can describe this situation as one where sender and received coordinate on a message.
When (2) obtains we can say the sender acted in a way that indicative of some fact or other and the received is recognizes this; (2) can obtain when one obtains as a separate signal or when the sender hasn't intended to send a signal.
(3) obtains when the receiver attributes to the sender some expressive behavior or information that is inaccurate, say, because an interpretive schema has characterized the sender and the coding system incorrectly producing an interpretation that is false.
Also remember that each recipient of the signal will have their own reaction to it. What signals professional competence to one person can signal lickspittle corporate toadying to another.
replyYes, but in aggregate, most people (or most groups of people) will arrive at the same conclusion for the same signal.
replyElse signals and signalling wouldn't be a thing and people wouldn't care for them, their reception would be a random scatter plot.