Hero of Ages Annotations- Unsolved Mystery?

[Quiver he/him]

So, I started reading Brandon's annotations for the Hero of Ages and found this passage:

 

Electrum

I held off on using this metal because while I knew what it had to do, I also knew that it would make atium far less important.

The way I built Allomancy, there is a logic to its framework. Atium shows other people’s futures. Gold shows your own past. Each group of metals has internal and external powers. Therefore, one of the two alloys (either atium’s or gold’s) had to show other people’s pasts—the Eleventh Metal from book one, an alloy of atium.

The final metal of that group, then, had to show your own future. I wanted this to be an alloy of atium. But the problem was that it couldn’t be. There is always a pushing metal and a pulling metal to each set. The pull always comes first; the push is always the alloy. The two external metals (that do things to other people) have to be grouped together, and the two internal metals (that do things to yourself) have to be grouped together.

That means atium and gold are both pulling metals, and the ones that do things toyou both had to be related to gold—and both metals that do things to other people had to be related to atium. Therefore, even though initial logic makes it seem that the alloy of atium should be the one that shows your own future, the way the magic is arranged means that it has to show other people’s pasts. [Editor’s note: Careful readers may intuit something else about this that Brandon is holding back.]

 

Anyone know what the editor's note is related to? It';s been a while since I read HoA, but I can't think of anything from later in the book that fit's the description (and it isn't spoilered, so I'm assuming that means it didn't become relevant)... so is this related to the broader magical system of the cosmere? Is there something going on here that I'm missing? 

[Voidus]

I believe it's a reference to Bendalloy and Cadmium being the metals which complete the temporal metals quadrant.

[Kurkistan he/him]

Perhaps also the fact that atium is a god metal, and isn't actually paired with gold?

[ThirdGen]

Perhaps the "does something to you" + "shows other people's pasts" means more that it actually transports you into the future in some sense and shows your possible alternate timeline selves' pasts.

[natc]

Electrum, Gold, Atium, Malatium. They allow you to "see" shadows of the past or future of yourself or other things, respectively (though the visual nature is probably just how the brain interprets it, like with inquisitors and steellines, since atium users can dodge things they aren't looking at too).

You see a problem here? The outside world remains untouched. With physical allomancy, tin and pewter augment your body in various ways, while iron and steel manipulate things other than yourself. Copper is an oddity (though I believe the emotional allomancy resistance only affects the smoker themselves, so I guess the "cloud" can be considered excess power leakage?), but bronze also alters your senses (to detect/identify investiture use).

It would make sense for the external temporal metals to manipulate time outside of yourself somehow, but all atium and malatium do is alter your personal perspective of time, regarding external objects. The power affects you, not the world. They're internal like gold and electrum are.

That sentence refers to this. And indeed, cadmium and bendalloy were discovered prior to AoL, accelerating and decelerating relative time around you respectively and causing us fans who like to get into physics to scratch our heads to this day.