Oh. I was just trying to shoot those birds with this here jello-shooter.
-noob using a fuel rod gun
Social Infection
I think that the flood encountering precursors in battle would only prove to end the flood. They wouldn't stand a chance. I also think that A gravemind only has access to knowledge from the infected in the planet it is on. If spores from other graveminds exchanged knowledge across the stars, then I think they would be able have more unified knowledge.
in terms of precursors creating the flood, this would make more sense. But also as they consume more lifeforms, they would become dumber. I think this because the flood too, must eventually degrade or die even if they have some sort of hibernation. If we are talking about millions of years ago, even the flood cannot remember, especially if they had no new food source to repopulate to sustain the memories and the gravemind(s). But if they consumed forerunners, then perhaps they relearned some old tricks, but far less potent. And even in the year 2552, they must also have lost some knowledge of the forerunners as well without food for THAT long as well. Like anything, biological or mechanical, memory or data need to be housed in a safe area that is being replenished so that the data or memory doesn't corrupt or get lost.
in terms of gravemind sentience, I remember somewhere learning that the gravemind builds and builds as the flood infect, and after a certain point, the building becomes lifelike and utilzes knowledge to be a mind of its own, but it always follows the same path of destruction, which is odd, that every time a gravemind forms it desires the same thing. I believe that the gravemind was built corruptly. Perhaps once it takes on too many conflicting personalities or the fragments of them, it becomes enraged within itself at its conflicting fragments, as the gravemind would be an impure being, where as if it was just holding the memories apart, it would not be in conflict. So it feeds on the hatred that the memroeis have of each other and act on all of them at once trying to consume all, which enrages it more as it gathers more conflicting thoughts. The precursors may have only gotten to the proto-flood as we know them, but were unable to contain them and study them for fixing them. They may not have had defense systems or weapons prompting them to flee the galaxy, but leaving behind the means to keep the flood at bay, hoping to one day have a species ready to combat them and return to the galaxy.
In terms of what you said of the gravemind being able(like perhaps a rampent AI) being able to find a loophole in its "programming" or rather DNA structure, this is acceptably true. If we look at human addiction, it compels a person to do something like drink alcohol, but just because your DNA says to do it, doesn't mean that with will power it can be resisted, at that point enough resistance makes the urge lie dormant, and so long as you don't indulge the extreme urge won't be there anymore. Biology is very complex, I think even for pre-cursors and they didn't get it right.
I would like also to point out in response to this as a whole, that perhaps the flood is at this point corrupted. At once point they may have looked nice and humanoid without disfigurement. They could have easily just been a parasite that would re-animate anything dead, rather than killing things and hosting the corpse. They would move the bodies to be categorized in the gravemind. But perhaps a mutation caused the flood to become rampant and slaughter, first starting within the flood itself, which could have given pre-cursors time to prepare, and then they would have begun their galactic conquest. If your theories of categorization of species or memories are true, then the current state of the flood wouldn't do that, a more pure version would though.
Don't draw parallels between games or other lore or stories. There are only 16 basic story plots, and if we try to make clever similarities saying, one copied the other or drew from another is some way, is entirely insulting to the creator, because we as humans only have so many basic plots to draw from, and all our stories are variations on it. Yes, halo is like a lot of stuff, but I wouldnt delve into it all.
In terms of a fourth dimension, people often think it is time, but I think time is a by-product in 3 dimesions from the forth dimension, or perhaps how we percieve the fourth dimension.
We use our eyes to understand 1-d 2-d and 3-d, so why not 4-d? I think it is perhaps being able to "see form other perspectives, being able to see (for example) earth from outer space but also be able to see billy eating cereal hastily before school starts and anything inbetween. Mass actually creates time(if you didn't know) mass spheres like planets create their own gravity because they are a disruption in space, this creates a pull towards its center. This gravitational field makes time go slower or faster. So on Earth, time is slower and people would live longer than on the planet Reach since it is slightly bigger. There are other factors that determine life spans, but for us this is true. I also believe that godlike beings are the only ones that can access the 4th dimension because they shield its knowledge from us as one of the many facets of being mortal. Anyhow, I think that if the precursors exist, then they are infact hiding from the flood and perhaps trying to find a way to kill them in one full on blow and preserve all other life rather than killing everything or having a method where they keep getting killed like the forerunners did, and like the humans are.
Nice thread OP.