The French weren't defeated in Spain because of logistical difficulties. Suchet campaigned capably in Eastern Spain and his troops were properly supplied, equipped, and fed.
You're overestimating the logistical problems while at the same time judging Napoleon's logistical system on the basis of Spain alone, which is incorrect. Swords has enough supporting material for logistics for a good beginning to research the subject, your inaccurate denigration of the work notwithstanding.
And sweeping statements are seldom, if ever, accurate.