Suppose someone knows that he will miss a day during Sefira (having surgery). Is it proper for him to count with a Bracha up until the day he will miss?
There is a concept brought in Hilchos Sefiras Haomer that one of the reasons women shouldn't make a Bracha is because they are likely to forget one day. Not sure if it stands Lehalacha, but it would appear to apply here (where the person knows for sure that he will miss).
[On the other hand, it might be different here because of the surgery aspect]
This is definitely an interesting question.
chacham ben tzion aba shaul in chelek alef-36 and chelek 3-16-5 understand the behag differently. he says even the behag agrees that its 49 seperate mitzvot . just that if you miss a day, youre lacking the continuous flow and therefore youre out. rav soloveichik is quoted also as understanding such. acc. to this , one can begin even if they know they will be unable to finish bec until you miss youve fulfilled seperate mitzvos. see there its a beautiful piece. however the Chida in more be'etzba 217 says that if you miss a day , then all of your berachos are retroactively levatala. so the chida seems to understand that its 1 big mtzva. accordingly, if one will be unable to finish, he should not begin. see daily halacha from rabbi eli mansour online - he has a quote from rav elyashiv on this there is a shiur by rav nissan kaplan on this forgot where .