Having taught DD who is a September baby, the basics, I wouldn't do it again.
DD was desperate to learn to read and we did some basic letter sounds. Nursery also did some of this with her, as they started all their preschool group on Jolly Phonics.
Before she started in the September, she knew most of the simple letter sounds and could read simple phonetic words i.e Cat, Pig, at, big etc.
However, when she started school, she didn't really progress and by the end of Reception I was actually worried about her progress, by Year 1, she was put on the Reading Recovery scheme, which she flew and there were no obvious problems with her reading, she just hadn't progressed.
I personally think that because she knew some sounds and words, she switched off in the class and then never really got it back. The teacher wasn't the best to be honest, but her Year 1 teacher spotted the problem immediately and rectified it.
If she hadn't known anything, would she have been more interested?