Question

Hello honored Rabbi, I wanted to ask how one should relate to an ordinance when there is disagreement about its real reason. That is, if there is a clear reason, then insofar as it applies, or there is doubt whether it applies, one continues to observe it; and if it absolutely certainly does not apply, one may consider stopping. But when the reason is unclear, what does one do?
 
Also, I would be glad to hear your opinion regarding two ordinances of Ezra the Scribe:
1. Eating garlic on Friday night — is the reason clearly to strengthen semen for marital relations on the Sabbath? If so, to your knowledge, has this reason been scientifically tested? If so, is one specifically required to eat garlic, or garlic along with other things that could help with this, or does it not matter what, as long as it helps with that? Do unmarried men also have to do this, because I have seen some who practice it, but that seems to contradict the reason.
2. Rising early to bake challahs — I saw one opinion that says the reason is not connected to the Sabbath, but rather whenever necessary, one should rise early and prepare so that there will be bread for the poor. The question is whether one can rely on that lone opinion for this reason. If so, what exactly does that say about the required times—what are those times when a woman is obligated to bake, and for what purpose?
 
Thank you very much in advance