Teaching Babies and Toddler Sign Language....My Experience

I am not an interpreter, nor do I know everything about sign language. I am only writing from my experience and expressing my opinions. When our son was about six months old, I started using simple signs along with saying the word so that he would put the two together. Almost immediately, he understood the sign for 'no' which at times was a big help. At about eight months old, he started using the signs. He was able to sign 'more' 'please' and 'thank you.' Although his 'more' meant either he wanted a drink or he wanted a snack. Now, lets jump ahead...he is now nineteen months old and knows the signs for the following words: more, yes, no, please, thank you, all done or all gone, hot, cold, happy, fan, cup, church, and a few more that I can't think of right at the moment. I know this list looks short, which in part is my fault for not continuing to teach him, but even with these few words, our life has been easier in that we are able to know what he is trying to say. He is know starting to say the word while signing the word. I do not feel like teaching him sign language has hindered his speech in any way. What are your thoughts on the matter...do you think teaching babies and toddlers sign language causes a speech delay? Have you taught your baby or toddler sign language?