Gittin 72: In the Case of My Future Death, Here is your Get

After ending their conversation about whether or not a get is valid if it is demanded verbally or through writing, we are introduced to a new Mishna.  The rabbis teach that the language of a husband must be very specific if he writes the get in advance of when he wants it to go into effect.  It is necessary for a get to be written and delivered before a husband's death.  Thus a man going overseas might want to have a get written and delivered before he leaves to ensure that his wife is not left an agunah.  But is he allowed to do this?  The rabbis question whether or not this is permitted if the husband writes that they are divorced as of that date in the case of his future death.

Such uncertainty is uncomfortable.  What about chalitza?  What about the husband who returns after a prolonged period, more than twelve months?  Our daf ends with the rabbis discussing what should be done if a husband offers a get in the case of his imminent death, but then he recovers enough to walk through the market.  In that case, the get is revoked.  But if he becomes ill again, is the get valid?  Was this the same illness or a new and different illness that ultimately killed the husband?