Sign sign every where a sign

I've been trying to teach kade to sign for MONTHS now, probably since he was about 6 months old with him showing very little interest. Now in the last few weeks it's really just like a switch flipped. He can sign "milk" and "more" and "all done" and "help." The American sign language sign for help is actually pretty tricky and involves what I think is a lot of coordination. You make a fist with one hand with your thumb up and place it on your other open palm and raise the two up. Soo... that seemed to difficult for a little boy just trying to figure out how to use one hand at at time. So i actually taught him the sign for "help I'm choking" instead. haha It's just patting the upper chest with both hands. Easy peasy. And he does it ALOT. It's very cute and pathetic when he looks at you and signs "help" for everything he wants, so it's hard not to cave, but I'm trying to teach him to be a problem solver at the same time and learn to do things for himself.
He also is a big fan of signing "all done" after about 30 seconds in his high chair. And he signs it emphatically! hands waving like crazy till he's literally red in the face. (He hates to sit still long enough to eat anything). As my mom told me, I guess the problem with communication is that sometimes you don't wanna hear what they have to say. :)
My pediatrician counseled me not to teach him to sign cause he told me that boys will cling to it, and then not learn to talk till later cause they already can communicate through sign.... uh? who here thinks it's a bad idea to teach their kid to communicate before they can talk to help them avoid frustration? I did alot of research and I've decided the doctors worries are old wives tales in my opinion and he can shove it. :)