There is also the possibility that Hood's weight (and Rake's weight for that matter) were just the proverbial drip that filled the bucket. you know, without Hood's weight Rake had no problem (or no noticeable problem anyways) to carry the sword, but with Hood in it, it just became too much. Not because Hood himself was giantly heavy, he just was that one kilo too much while Rake could only handle another 0.01kilo.. (or pound too much while Rake could only handle another 0.01pounds, if you prefer this measurement).
This of course is not a theory most Hood lovers will like because it inclines their favorite (ex)God isn't necesairly too great at all (to expand my metaphor: it could well be, if my theory is correct, that Hood only weighed like 0.02kilos/pounds).
Ah well, I personally still like to believe Hood wasn't that heavy at all, it's just the dead army (which followed Hood of course) that made Rake buckle under the weight. Why then was Rake so heavy when he came in? A fresh theory springs to mind as I type this:
Pearl muses somewhere in TtH that only the good of the souls remain chained in Dragnipur, the bad part of their souls goes straight to the Chaos chasing them. Now, let's take Pearl for example: a major demon, probably a bit more evil than good, so he shouldn't weigh that much to Dragnipur since he'll mostly be chaos (which we assume has no weight at all since it technically doesn't exist). Draconus: same thing, mainly bad, so not too much weight either. Then we come to Rake. Rake was a badass guy, but in his true core was a very good person, never did something for himself, did everything for his people and even others too. That's why, when Rake ended up in Dragnipur, a huge weight comes down: Rake has barely any part of his soul that goes straight to Chaos and thus the biggest weight of his soul goes to Dragnipur and thus remains its weight.
How then about Hood? Well, Hood was a freaking God of death, one can imagine him not having a too pure soul. As a result Hood himself doesn't really weigh that much to Dragnipur. What does weigh that much, however, are the dead people following him. How come? Simple: the dead are pure.
Even though my last theory seems flawed (I mean, it must be, I cannot possibly believe I have just stumbled upon a truth

) I'll leave it at that and post it anyways, perhaps some of you can point out where my theory is flawed and perhaps even can correct it.
PS: I wondered this, about Hood, ever since reading TtH: now that all souls will be released from Dragnipur, so too will Hood... will Hood still be God of Death then? Or has he truely retired and will he now... dunnow... no longer partake in the story?