It seems to me that learning material over a long period of time is better than just "crashing" for exams, which this author's proposed system would encourage.
It is easy to imagine that a student will skip an assignment at one point, then stop doing homework altogether. The student will realize he should have done the homework toward the end when he realizes his grade, but by then it will be too late -- his homework average will be too low to make a difference.
His suggestion just saves the people who already know the material or who learn in other ways than homework from being penalized by having to do a ton of pointless busy work. If a person who thinks they can learn the material without doing the homework ends up trying to cram and then failing the test, that's his/her own problem. That person should just do the homework unless they're sure that they can learn the material without the homework.
I don't think it is only their own problem. Many people in school simply cannot recognize when doing the homework is necessary to learn the material versus when they already sufficiently understand it. Good teachers actually teach students how to learn effectively, and can help recognize how a student learns best.
It seems that the prevalence of homework => test in schools today is a result mainly of larger class sizes requiring the teacher to make compromises for students with varying levels of ability, motivation, and parental involvement.
Then they should just always do the homework and be on the safe side. Anyway, even if they screw up once and think they can get by without the homework, that's one F and they'll quickly figure out that that approach doesn't work for them.
It is easy to imagine that a student will skip an assignment at one point, then stop doing homework altogether. The student will realize he should have done the homework toward the end when he realizes his grade, but by then it will be too late -- his homework average will be too low to make a difference.