Lynn,
I am probably not one to comment on the life-force sucking machine and how it might or might not help as I am a non-believer in DC's premise of how Clark's heart could have become compromised.
That said Bernie said (in BU) that he had already compensated for the energy drain and Clark made reference to losing a few years for a friend. The take around here was that he lost around a decade of life. Now if you take some of the examples of FanFiction around here (Home Series, Lonely is the Man, etc) it seems that Clark would live to be over 200 so say 200 is his normal life expectancy (it is actually probably more) and he lost 10 years to Jimmy and Schenk then he lost around 5% of his life force (which Klein thought he had already replenished). But for the sake of argument he lost 5%. Now if his heart is now damaged beyond any repair I fail to see how regaining 5% of his life force will repair it by itself. I am sorry but the life-force machine should not have any appreciable effect on Clark and his condition. I am sorry I am a techie who can suspend certain beliefs in the name of science fiction but if his heart has failed and his regeneration has failed to fix it he should not invulnerable or have much of any of his superpowers as they appear to be all tied together. Since I tend to not like death fics that is one of the reasons I am still reading this one.
In the end I believe (as you) DC will sacrifice someone to save Clark and allow him to live to see his son grow up and my expectation is that she will write an ending full of hope and remembrance of the person who sacrificed his (or her) life. Since DC made a point about the name of the baby and the baby is a boy I doubt if it will be Ellen
.
This next chapter (Part 8) while very interesting as a setup is not what keeps me here. By the fact there are two additional parts after the death I expect the heart (pun intended) of the story will be in those parts and that is what I eagerly await.
Mike
(This is in no way a hint, btw.)