see I think #3 is right-on, as I've also heard that UC tends to lessen with age. By that I mean, people who were diagnosed early in life, have had UC for years, then it seems to taper off on it's own. It also makes sense because as we age, our immune systems age right along with us, they don't work as well or as quickly, therefore one would think that the immune system itself would "burn out", so to speak. I've never heard of someone having just one bad flare & then no more though.
#1- no clue if that's correct or not... I guess it could be, it sounds good!
#2- I believe this too, because if you look into probiotics, the makers of those say the same thing- that the immune system constantly is attacking our digestive tract, trying to get rid of the bad bacteria. So if anything funky is going on with your immune system, it very well may not know when to quit & just keep attacking.