What happens when you have a 4+ year old just hovering at 1300-1400 grams, short and stout, not eating a lot, but enough that she's in fine physical shape...are you just never going to breed her?
It doesn't just boil down to being impatient. I started pairing my cinny girl at 1,800 grams and 18 months old after I felt follicles developing and did not feel that I was putting her at any extra risk. I have older females that I did not breed because I was not too thrilled with their behavior. I'm comfortable with dealing with my snakes on an individual basis rather than going by a blanket of rules that cover all of them.
I just had a 3 yr old female that's barely made it to 1200g before laying and gave me 5 perfect eggs and went all the way down to 780g after laying. She is healthy as can be and pounding rats...