In my opinion, hearing "Sign's Up!" is like hearing fingernails raked across a chalk board....yes, it's that annoying. It is unnecessary, not needed, and uncalled for. In fact, in the Troop Leader Guidebook: Volume I, it states, "Adults should never Yell "Sign's Up!" The Scout sign is a silent signal, and getting control of the group is the senior patrol leader's responsibility."
Seems pretty straight forward, doesn't it? It's a silent signal. That fact was stressed during my Wood Badge course. Day 1, first time the sign went up by one of the staff, someone yelled, "Sign's Up!" That staff member quickly nipped that in the bud. He explained that it was not necessary to yell "Sign's Up," that the mere action of putting the sign up is sufficient. Furthermore, if you are going to yell "Sign's Up," there's actually no point to put the sign up. It now becomes a yelling match to see who can be the loudest. That will accomplish nothing in a Scout meeting.
I know what you are thinking, "I have things to cover, I have a schedule to keep." I get it, but it isn't setting a good example. On top of that, it shows everyone you have a lack of patience. Yep, it takes patience to stand there with your arm up, waiting on the boys, parents, siblings, and sometimes leaders to quiet down and pay attention. But it needs to be done that way. You need to stand there silently, as long as it takes, waiting patiently for the room to get quiet, for the boys to direct their attention to the right place so you can start the meeting, pass the word, or pray over the meal, whatever it is that you are trying to accomplish. In the end, it's worth it. Eventually, the boys will learn that things will go smoother and faster if they are paying attention and quiet down quickly when the sign goes up.
So, Den Leaders, let's "Do our Best" to help the Cubmaster during Pack Meetings by paying attention and be on the ready to throw the sign up when needed. Patrol Leaders, "Be Prepared" to raise your hand when the SPL or Scoutmaster addresses the Troop. We can all do our part maintaining our silence within the aspect of this Scouting tradition.