She was not writing for a philosophical journal.
If you ever attend one of her talks directed to physicians, as I did, you will be pleased to note her more than passing nod to Aquinas and scholastic philosophy as well as her systematic approach.
However, its a bit disengenuous to demand same from an article aimed at an entirely different audience.
I have attended one of her talks. At the time I was a big fan and ready to be impressed. But instead I was quite disappointed. Actually, it was her tape "Contraception, Why Not?" that first opened my eyes. I could see that not only were her ideas muddled, but she was not presenting an authentic alternative to contraception. Instead she was mostly shilling for NFP.
In fairness I must say that the talk I attended in person was superior to her tape. I think her ideas have progressed and improved. But they have not gotten any more systematic. I defy anyone to draw an outline of the talk she gave. It meandered and jumped back and forth. It did not demonstrate the clarity of order that should be the hallmark of a follower of the Angelic doctor.
Who is her audience? Is it college students she is trying to prevent from committing the sin of fornication, or is it married or engaged couples? I'm having a tough time discerning just who this talk was aimed at.