Signals from the coach to the pitcher

[Rufus]

We're an 11U rec team playing under USSSA and are 8 games into a 10 game season. A couple of our pitchers are capable of throwing different pitches (4- and 2-seam fastballs, change ups) as well as pick-offs. For these couple I call the pitches from the dugout. For the first time last night the PU informed me that I wasn't allowed to do that and that I had to signal to the catcher who would, in turn, signal to the pitcher.

I found the following reference in the USSSA rulebook in 8.08.A

Pitchers shall take signs from the catcher while standing on the rubber.

The rule then goes into great detail about the windup and set positions, and how a balk can be called, but never addresses what happens if the pitcher receives signs from someone other than the catcher. A couple of questions:

• Is there a penalty to doing this? The PU said he would have to do "something" if the opposing coach makes a stink and I was sufficiently chastened that I didn't think to ask what "something" was.
• Can the pitcher stay off the rubber, receive signs from me, reingage the rubber, then pitch (as long as he doesn't try to "quick pitch")?
• While I know I have to adhere to the rule, and the origin doesn't make much difference in the grand scheme of things, can anyone tell me why this rule is in effect? Is it the same in FED and NCAA?

I know my catchers should be able to do something like this but, to be honest, I'm not sure the catchers I have would be able to handle it (though I may be underestimating them).

Thanks.