Baba Kama 24a - Kiruv Nigichosav and Richeik Nigochosav

The Tur (O.C. 144) writes that the Maharam M'Rottenberg who would say 90 times on Shemini Atzeres "mashiv ha'ruach u'morid ha'geshem' to create a chazaka. His logic was that if 3 times a day for 30 days works, then certainly it would work when it is said on one day 90 times. His proof is from our mishna where R' Meir holds that if an animal can become a mu'ad for goring once a day for 3 consecutive days, certainly it can be a mu'ad for goring 3 times in one day. However, Rabbeinu Peretz argues because the logic only makes sense for an animal turning into a mu'ad, where the logic dictates that the closer in time that the gorings take place, the more prone the animal is to gore. But, davening is dependent on one becoming accustomed to saying "mashiv haru'ach" and the time of 30 day may be a significant factor in changing one's habit.

The Beis Yosef quotes in the name of R"I Abuhav, that the Rosh agrees with the Maharam and rejects the distinction made by Rabbeinu Peretz. His rationale is that even the "הרגל הלשון" is also based on changing the nature of a person from what he was accustomed to until now, and therefore it is exactly the same as an ox turning from tam to mu'ad.

It seems that the machlokes maharam and Rabbeinu Peretz is dependent on the rationale of why an ox becomes a mu'ad after 3 times. It is clear from the gemara 15a that a mu'ad is considered an ox that is natural to gore. The question is, does the 3 times goring change the nature of the animal from tam to mu'ad or does it reveal that all along this animal had a bad nature that causes it to gore. If we assume like the first approach that it is a change in the nature of the animal, it is exactly the same as changing one's nature from their being accustomed to not saying mashiv haru'ach (as the R"i Abuhav explains that they are both based on changing the nature) and therefore we can apply R' Meir's kal v'chomer. But if we assume that R' Meir's kal v'chomer only applies to a case where we are trying to show that the animal was always a goring animal, we cannot learn from there that the "kiruv ni'gichos" helps to change the nature from what it was (which is the opinion of Rabbeinu Peretz).

R' Shlomo Eiger asks how we can learn anything from R' Meir since we pasken like the Rabbonon who reject his kal v'chomer? Perhaps the Rabbonon don't reject the logic of the kal v'chomer, rather they assume that the pesukim by mu'ad demand that it be over the course of 3 days.In a case where the pesukim indicate it has to be spread out, the Rabbonon insist on it being spread out, but in the context of mashiv ha'ruach they would agree with R' Meir's logic. Their proof from zavah is not that we reject R' Meir's logic in general, rather that we take the pesukim as is in that context, and assume it is a gezeiras hakasuv to take it as is in this context.