Dear Brother, my two cents.
The purpose of fasting is clearly mentioned in Quran. That is to attain Taqwa. The book Quran is for those who are "mutaqeen." Taqwa, in simple language is to stay upright, to follow God's mandated commandments in all circumstances. Saum is therefore a training to enable us to attain self control and discipline how to obey God's commands. Please pay attention to what is being asked in Saum? To stay away from things which are halal, permissible. If we can do this, then certainly we have developed the capacity to abstain from what is impermissible or Haram. If one does not develop capacity to stay away from Haram after this training, the purpose of Saum is compromised. I have yet to see Muslim scholars fully emphasizing and addressing this aspect. Muslim scholars (if I can call them so) are busy telling them they are getting Tawab, reward from God. None is explaining to them that reward is inbuilt in the action itself in the form of "capacity development." That this "capacity development" will not only carry them through this life with honor and dignity (to borrow the words from Dr. Sahib) but will also propel them higher and higher in the life to come.
Please bring to mind the training soldiers go through? What is the purpose of their training? Isn't it to develop discipline, to enhance capacity to bear the difficulties and hardships during war, and to remain steadfast in obeying the commands issued to them from their superiors during both peace and war?