Aside from the ch'hai gavna of "chur d'bein y'hudi v'armai", is there a nafka minah from the machlokes between Plimo and the Rabbanan? Unless this is a machlokes in m'tzi'us, it would appear that Plimo and the Rabbanan argue on whether we hold "sh'chiach hezeika sha'nei." If so, there would be many potential cases where Plimo and the Rabbanan would argue about sakana when performing a mitzvah. Also, what is the geder of "sh'chiach hezeika"? According to Rabbeinu Chananel, "b'makom she'yeish hezeik kavu'a" we don't rely on protection from mitzvos. What is the geder of kavu'a? The Rosh (Pesachim, siman 13) uses the lashon of "ika sakana" to describe "sh'chiach hezeika"? What does that mean, practically?

The only m'koros that I have seen explicitly define a clearer geder of "sh'chiach hezeika" are the Kovetz Shiurim of R' Elchonon (Pesachim, siman 32, who, based on Rashi, defines "sh'chiach" as "rov memisin" [assuming that one additionally knows that the cause of danger is present]) and the Ramchal in Mesillas Yesharim (perek 9, b'vei'ur mafsidei z'rizus) who writes "Makom shehahezeik matzui v'noda yeish lishameir... ha eino m'daber ela b'nistar min ha'ra'ah asher ro'eh, lo mimah sheyuchal lihyos sheyihyeh efshari sheyavo," but doesn't indicate that "rov memisin" is required for "sh'chiach hezeika." Perhaps this Ramchal follows the position of R' Chananel. It also seems possible that R' Elchonon could fit in with the Rosh: The sugya that R' Elchonon refers to is "aval akrav posek" (B'rachos 33a). Rashi over there, who holds that rov is a significant condition for "sh'chiach hezeika," uses the lashon of "l'fi she'akrav m'sukan" to explain why one must interrupt his t'fillah. Thus, it seems that the term sakana applied generally can refer to "rov memisin." This is further indicated by the Mishnah Berurah's lashon regarding "nachash karuch al akeivo" (104:10), where he writes "d'min hastam lo yihyeh sakana," having written in the Bi'ur Halacha (D"H "va'afilu nachash") "mishum d'rov p'amim eino noshech" (based on Rashi and the Rambam. The Bi'ur Halacha follows this with the following quote from the Magen Giborim: "Uvmakom sheyeish chashash shemeimis, havei nachash k'mo akrav." Apparently "chashash" here means rov.) However, it still seems possible that the Rosh could have different standards than Rashi for what he considers sakana. Does the Rosh elsewhere indicate his position?

Would it be valid to say that R' Elchonon and the Ramchal argue, and that they hold like Rashi and R' Chananel respectively? If so, what would be the nafka minah. Could it be that R' Chananel would understand the case there of "nachash karuch al akeivo" as referring to a type of snake that is not dangerous (such as the type of snake discussed in maseches Shabbos [107] that it is mutar to trap, but assur to kill [see also Magen Avraham 316:12]), and that the akrav discussed is less than "rov memisin"? (I don't have a Brachos or Shabbos available at the moment, and I don't know if R' Chananel speaks explicitly on this topic in those masechtos). Also see Mishnah Berurah (433:35) on sakanas akrav versus sakanas nachash, which seems to fit with R' Elchonon's approach. Clarification would be greatly appreciated.

Also, according to the Magid Mishnah, the Rambam (Hil. Chametz u'Matzah, 2:5) holds like the Rabbanan who argue with Plimo, despite that our girsa in the Rambam follows Plimo, as the Kesef Mishna points out. Within the Magid Mishnah's girsa of the Rambam, the Shiltei HaGiborim suggests, contrary to the Magid Mishnah, that the Rambam did hold like Plimo. The Shiltei HaGiborim apparently explains that the Rambam didn't mention the case of "chur d'bein y'hudi v'armai" because he held that it is obvious that we follow Plimo because of the gemara (Chullin 10a) that says "sakanta chamira me'isura"? What's the connection? How does this show that mitzvos protect one from sakana? Is he trying to say that if "azlinan basar ruba" regarding establishing the metzius of a cheftza to determine if an issur applies to it (Chullin 11b), than certainly we use rov in establishing something as a sakana (and that just as one may not perform a mitzvah through an issur, such as lulav hagazul, one also may not perform a mitzvah through a sakana)? [Even though "ain holchin b'piku'ach nefesh achar harov", we could still use rov to determine if something is considered a full-fledged sakana that we treat as a vadai sakana. Piku'ach nefesh, however, doesn't require a definite sakana.] If so, would that imply that a mitzvah performed through sakana (such as davening in the presence of an akrav) would be invalid? Is a mitzvah ha'ba'ah b'isur asei invalid in general? (Unfortunately, I also currently don't have access to a maseches Chullin or Sukkah, which somewhat hamstrings further iyun.) Also, is it possible to infer that the Rosh might support this Shiltei HaGiborim from the Rosh's remarks on Pesachim (siman 13): "Since there is a sakana, we go according to Plimo"? Does this imply that we follow Plimo because his position fits with an already accepted halacha?

Thanks in advance for your time and expertise.