It seems to me that these schedules assume several things…
You don’t have a full time job, a family or children, the sun shines every day, you never have to work overtime, you never get sick or injured, your kids never get sick, you actually have 18 weeks to devote to an such aspiration and you have the will to complete the training required to finish a marathon.
But despite all the assumptions that piece of paper makes we still manage to spend 18 weeks running and worrying about that one day where we make the 18 weeks pay off. And we all know about assuming things. To wit:
Who needs law school anyway?