He most likely left out those which are not spoilerish in the course of reading the book, but that would tell a little too much if read out of context (eg titles like "A wedding", "Blood and Fire" - not spoilerish in the book when it's been foreshadowed chapters before, but it still tells you too much before you start the book).

Harriet also has a good track record for finding titles that sound terribly obvious (often those in the "gasp!" category), but which are most of the time misleading, while when we should gasp, the chapter title is often innocuous. I'd be especially wary of something like "The End of a Legend". It way too obviously could mean "The Death of Cadsuane", and unless Cadsuane is on her death bed the scene before and it's no surprise when she dies, that'd be most un-Harriet like to be so blunt about her upcoming death scene (which was pretty much the first thing I commented last year when I heard of The Death of Tuon: "well, one thing we know is that Tuon for sure isn't gonna die with a chapter title like that"...).

It could still be an ending of some kind for Cadsuane (she might do something to put an end to her own legend among her circle. In truth, she's got herself a little trapped for using her legendary status a little too freely lately... this chapter could be her mea culpa POV, for example her reunion with Rand that turns into mutual apologies, and introduces to us what Cadsuane still has to teach him and the Asha'man.

I've speculated in an "apology scene" she might come to reveal to Rand how exactly Toothie has shaped her up and made her the formidable woman she is, and how she had hoped to do the same thing to Rand, to make him a leader instead of an arrogant prick, but has failed. "Have you, really?", post DM Rand might answer back). My theory is that Cadsuane's youth story is of the rather humiliating kind. Imagine newly raised Cadsuane, fleeing the Tower before she gets saddled to something by the Ajah Head, hunting for a warder but being choosy, wandering alone with not enough care to have adventures, and ending up in a little isolated village in the Black Hills, where in the full arrogance of her new shawl and great strength she's decided the old Wisdom there didn't keep a low enough profile for a non-AS (and perhaps was training one or two apprentices...). Young Cadsuane decided to bring her down a few notches and put the fear of the Light in this wilder (an minor alternate version to that would be that she found out Toothie was humanely keeping an eye on a young male sparker from her village - both to keep him safe as long as possible before kindly "putting him to sleep" when madness showed, and to spare him the horror of being caught by Red AS, treated as criminal then abandonned to die. That's the sort of behaviour Nynaeve the Wisdom would have been capable of.

It could be Toothie who shaped Cadsuane's views of male channellers, and showed Cadsuane to be kind to them, but not blind to the danger they represent either....

In the face of Toothie Cadsuane's strength, even her ability at all were meaningless because of Toothie's paralis net - and Cadsuane ended up a prisoner of the old Wilder, who over months taught her what the WT had not managed to teach her, about her strength, her character, authority, that her ability won't always be enough to protect her from ending in a pickle if she's too arrogant or careless, and so on (perhaps about male channellers too, as I said). As Cadsuane progressed, Toothie was giving her her jewellry bit by bit, as Toothie knew her end was near.

Such a scenario would end up tying Cadsuane to Nynaeve's back story as Wisdom (especially if Nynaeve starts to stand up to Cadsuane... she could remind her of Toothie...) as well as to her intro scene in New Spring with Moiraine. If there's a male channeller involved in the adventure, it would also tie Cadsuane to Rand's story, the Asha'man - and perhaps hold the seed of what Cadsuane wants to teach the male channellers. Ending up captured and broken by Toothie, her ability negated, would also tie with Semirhage's last weeks, Rand's capture in Far Madding... and the way Rand treated Cadsuane would also go back to her humiliation by Toothie, and after Tam Cadsuane might remember the lesson and admit to herself she made the same mistake she did in that village all those years ago, and paid again for it. Faced with Tam and Nyaneve, this would also remind her of her experience in the Black Hills village, where perhaps all the villagers decided to take Toothie's side against the arrogant Aes Sedai (echoes of EOTW in there too).

Telling this story to someone would put an "end to the Legend" of Cadsuane the Invicible for that person (be it Rand, or Nynaeve, or the WO), or perhaps it's just Cadsuane who reflects she's ending her legend telling the truth about this.

An alternate solution is that this chapter is the one in which Nynaeve finally manages to grab publicly the tiller from Cadsuane by putting her in her place after Rand vanished (and tell herself at the end, "well, I guess today I put an end to a Legend"... or maybe started a new one...), and take the lead of the AS in Tear. By the WT system, it's her right - if she wishes the authority over all sisters there including Cadsuane, it's hers for the taking, and not being recognized as a sister (because like those in Ebou Dar they're all too aware if they did, they just put themselves under her authority!!!). One thing for sure, there's a Nynaeve-Cadsuane confrontation coming (I'm far more doubtful there's a Moiraine-Cadsuane one... I just don't see the point, and I don't see how Jordan could possibly have had in mind to put Moiraine above Nynaeve so far near the end... Nynaeve is clearly the "heir" of Moiraine and Cadsuane as the AS near Rand, and she has to come into her own and put those two in her shadow before the end. I tend to think Nynaeve will resolve her issues with Moiraine as an adult, and that leaves a battle of wills with Cadsuane. After what Cadsuane did, using Nynaeve, it shouldn't be long in coming, as Nynaeve seeks to repair the damages done with Tam, then try to find Rand). If the confrontation is foreshadowed in a previous scene, a chapter called The End of a Legend would play on expectations: "surely Nynaeve can't kill Cadsuane, or could she?"

A non-Cadsuane possibility for this chapter is from TGS. Brandon established this silly gag about Mat setting up "legends". Perhaps it's a return to that (gods forbid - it's one of the most unfunny and bad scenes in the whole book, but it's possible). A possibility is that this doesn't related to Mat's silly "legends" directly, but it's that meaning to Legend Harriet was referring to in this chapter. For instance, it could be the chapter in which the "legend" a Forsaken has built for her/himself is unravelled. I would say unlikely, if not for the fact this meaning to "legend" (that belongs to modern espionnage - quite out of place in WOT, if you ask me) was well established in TGS and Harriet let the modern meaning slide.

Yet another is a Thom POV. Surely there's no shortage of possibilities (most of which we can't puzzle out now) for the gleeman to reflect he's seeing the end of a legend in something he witnesses. It could be a Caemlyn legendary thing (in a very mundane way, it could be something as simple as seing the Queen's Blessing closed down, well not that, but something else in the city he finds puts an end to an era).

A very surprising possibility would concern the Band of the Red Hand's demise. Perhaps against all odds they will be annihilated in the battle of Caemlyn, defending Elayne as before they died at Aemon's side to protect Ellisande and the flight of her people, fulfilling the "severed hand, not hers" viewing. With the Band in Caemlyn, we know Elayne's ties to them are coming soon, one way or another (some have suggested by the time Mat reaches Caemlyn, he'll find out Elayne/Brigitte have, in emulation of Roedran, made an offer to hire the Band, and the commander of the first half accepted... or at least he agreed to report regularly to Elayne, and camp where she would have them (not close to the walls), and treats her like well... the Queen in her palace, binding Mat to do the same when he arrives. He would be... so pleased.