Good question, I think that depends on your phone/settings. If it's just silencing, probably not as to the caller it will keep ringing until VM picks up. If it's declined, that may go straight to VM and the caller may notice a shorter ring and connect the dots.

Edit: autocorrect likes to have a laugh

When I was 12-13, I had a period of time where I absolutely could not cut through a pepperoni. What I did was to move the slices around before baking, however. This is the work of a sick mind.