Is music notation taught at the very beginning of learning or is it delayed by six months or longer?

A music student is at a distinct disadvantage if learning to read music is delayed. All music knowledge and technique comes from learning how to read music notation. It gives the student the ability to play the songs he/she would like to play. 

Too much time and money is wasted as a result of lessons consisting of songs, chords and tablature reading only. Very little useful knowledge is taught in such lessons. Learning tablature is not reading music.