I hope no one mind to respond in English since I have difficulties writing in Arabic from keyboard.
Well I once was a teacher in Intermediate school but not officent one, only as a drill since I'm in college. All students aren't one or have the same way of thinking as other do and this kind of rule has an dvantages and disadvantages. To be more clear, some students aren't encouraged well to start their new day at early morning studying 7 subjects or more with no breaks in between except that break time which last 15min if I wasn't wrong. Some teachers start making them concentrate on their subjects and because of the narrow period of time, they force them to do well. As you know teachers are tested through the improvment of students by their grades, participation..etc and some lazy and careless teachers start threatening students by marks and such thing so they can keep teaching even if they're not worthy, unfortunatily. Anyway as there are teachers like that there are good one and well experience.
However to my point of view I think being restrictive to take top grades or high grades is nothing compared to those who recieve and apply what they were tought. That rule which keep students push themslves to be always on top will memorize things and might understand but wont this wont last for long unlike when they recieve information in interesting way which will remain in mind for a long time.
Over-reacted in challenging make the atmosphere anixety and fear might grabs inside those weak students then they might lose hope on giving their best.
This violent way to be an excellent student wont gain any benefit further more even with its limit advantages.
I am not an experience person but that what I felt as a student and temporary teacher ^___^