bughtmaster, while you are correct in principle, I will tell you a story from my own refereeing experience.
I was assistant in an Austrian 5th tier match when the away goalie tackled a forward inside the area about 15 yards away from me, clearly playing the ball for a throw-in which I signalled. To everybody's surprise the main ref who was running on the other side of the pitch and had about 10 players between him and the action gave a penalty. I tried everything to show him that he was wrong, stayed on the sideline instead of going to the place the assistant has to stand at a penalty, waved the signal for throw-in and even tried to call him over, but he didn't even look at me despite several away players asking him to talk to me. Assistants cannot leave the sideline to run over to the main referee to tell them what they have seen, the walking has to be done the other way round, and with a good reason.
After the match, the supervisor came into our changing room and asked the ref what I had signalled in that penalty situtation. The answer was that he had been that sure of his decision that he hadn't been interested in my signalling.