That’s right. We can easily apply anything that anyone ever said to anything else we want it to apply to.
Rebbe Yid, I can’t be certain considering this is the written word, but my sarcasm detector went off when reading this line. I don’t know if you read the sefer that I linked to, but I was certainly not saying that we can apply anything anyone ever said to anything we want. What I was saying is that if someone had a certain sevara and applied it to case A and the similarities between case A and case B are such that the sevara would be equally applicable to case B, we can apply it to case B even though the originator of the sevara never directly addressed case B. ?????? ????, R’ Yaakov Levinson mentioned an objection to the suggestion that at the wedding, the husband should appoint the wife as a shliach. His objection was not an objection to the halachic mechanism, so there is no issue if the mechanism of the prenup is different; his objection was that bringing up a discussion of divorce/mean husbands during the happiest moment of her life is a bad idea. The prenup and the shliach suggestion are similar in that regard – they both bring up the same discussion at the wedding. The only difference is the halachic mechanism by which it seeks to resolve the potential problems. Thus, it would be very reasonable to assume that R’ Levinson would have the same problem with the prenup as he had with the shliach sugestion. That is not to say that there is no way to avoid his objection, nor is it to say that anyone is bound by his objection. It is simply to say that there is a sevara against bringing up certain discussions during the wedding.