As most of the people who have followed my blogs [BettyAtkins was "The Old Hooker"], I crochet with measurements, not stitch counts. I have two granddaughters who learned to crochet this way. One is 19 and the other 20. They have been crocheting since they were around 12-13. The 19 yr old came by the other day wearing a really cute hat that has a finished design of rows of hdc that bulges out and one row that sinks in to create an indentation... think of the design of a pumpkin. I was amazed that she was at the stage of designing already. That may be because I taught the eldest g-daughter and she taught the younger one.