Hi M.,
There are so many issues involved here, but I don't think the subject is ignored.
The "waiting for the child movement" please. My daughter would still be breast feeding if I let her and she's eleven. She loved it so much. People forget that both Mother and child have to be comfortable - not just the child. My daugher hated wet diapers and I had her potty trained by 18 months. She would rip the diaper off if it got wet. She ran around nake alot. The "nake kids" potty train early.
If baby is lazy and parent is lazy (which I have seen) the kids can be 3 to 5 before they are fully potty trained. Also many parents work and that can delay potty training.
If you are ready to began potty training - begin. With my daughter when I went, she went. She never let me go to the bathroom alone, so I gave her a book and told her to sit on the potty and she did. Once she peed in the potty and was so shocked and it was totally by accident. For boys if dad goes send your son inside with him. Boys take longer with moms and girls take longer with dads.
The first part of potty training is just having the child do what you do in the bathroom. The fun parts, like flushing, washing your hands etc.