More About "Mesorah" That's Been Bothering Me

See this is part of what I had in mind yesterday in the post about no commentary on Chamisha Chumshei Torah and Mesorah. Maybe I didn't say this part clearly, but this is part of the issue. Someone decided to say something, so it MUST have been true.
DovBear had an interesting post about Birchas Hachama, an event that comes around once every twenty-eight years. Next year will be that year, and, even more rare, it will happen on Erev Pesach. DovBear links to a post that links to a scan of a statement by some Rebbe or another that an Erev Pesach Birchas Hachama has only happened twice in history, the year of the Exodus from Egypt and the year Haman was hanged. The entire statement is false, by the way. There was no Birchas Hachama the year of the Exodus, let alone one ON Erev Pesach. Further, it's happened at least twelve times in history. Click for Little Foxling's post, and click "click" to see this Rebbele's statement.

This is one of the things that bothers me as well. Some guy comes along, he's a rabbi, so he has authority, and decides "such and such" is the reality. And it's completely accepted for hundreds of years. And this person presents NO evidence to back his claim. And it's wrong.

When a one writes a scientific or scholarly paper, we expect that person to provide sources, research, and proof, or at least evidence, to back up that person's thesis. In many Jewish writings, we don't get that.

Example: The SEMAK, in the 13th century, stated the minhag of kitniyos had been in effect from the days of Chazal. However, he brings no evidence for this. He just makes a blanket statement and we are expected to simply take it at face value and believe it. See this article about Kitniyos. Another example is the one about Birchas Hachama that Little Foxling presents in his post. Because some Rebbele said it, it MUST be true (clarification - Little Foxling proved this to NOT be true - in fact the phrase he chose was that is was "complete and utter crap").

Another is an example from Rashi. Rashi makes a statement that women do not become pregnant from one "encounter." He says this regarding the daughters of Lot, and states while usually women do NOT become pregnant from the just one encounter, the daughters of Lot had mastery over their bodies and were able to ovulate on command and become pregnant from just one "encounter" with their father.

And that's just PURE rubbish. Of COURSE a woman can become pregnant after just one time. All it takes is ONE sperm at the right time. Just ONE.

So why do we expect less from our scholars than the world does from theirs? Why do our scholars NOT need to provide evidence to back up their statements? Why are supposed to just trust them? How iss this NOT a form of mind control, especially when so many of their statements have been proven false?