The negative symptoms of garlic consumption, as described and criticised by Bob Beck, sound to me like standard Herxheimer symptoms; and as you said, garlic has been used for centuries and was revered by the Ancient Egyptians and Ancient Greeks (as well as the onion, of course). I am more inclined to heed the words of those living thousands of years ago than those living now. Besides, severe side-effects are sure signs of "die-off", in my humble opinion.