It's a perspective thing. You can read the Heart of the World to know how it fits. Why it fits in his trap is hypothesized by Vivec in his Teachings, but then, Vivec thinks the trap was wonderful. It has to do with a rebel wanting to be king.

Esteemed Loremasters,

Okay this conversation is waaaay over my head but I want to ask something anyway. This all goes back to the weakening of the boundries between Mundus and Oblivion (e.g. the Dragonfires/White Gold tower and the fire's/Amulet's replacement by the statue of Akatosh). Could the problem with the Red Tower (Red Mountain is simply no longer there - though the Heart may be (the enchantments were removed but the Heart was not destroyed)) and the death of the Mane (who himself may be a Tower or Stone) have weakened the boundries enough to allow Umbriel quasi-entrance into Mundus? By connecting Umbriel to White Gold is it Vuhon's intention to bring Umbriel fully into Mundus, perhaps therby creating a (more(-ish)) permanent gateway from Oblivion to Mundus? Or is the danger that a fully incorporated Umbriel will gain access to the creatia-molding powers of the Tower e.g. giving Vuhon the ability to shape creation as he wills? Am I anywere close here?

Also, I suspect Nu-hatta's concern about the Ayleids return was a reference to Umaril and the Knights of the Nine quests.

Your servant,

Scourgicus the Mighty

"Ayleid," as Nu-Hatta used it, meant conspirators. These were Umaril and the Mythic Dawn.

Vuhon may be planning to phase into Mundus, basically poping the bubble of Vile Umbriel's traqed in. White-Gold the structure would be destroyed, in my estimation, but I think its function was already lost in Oblivion. We'd have a new Imperial City, and a cooler one, I think. That wouldn't make a gateway to Oblivion. Cyrodiil's devestation might foreshadow a re-alignment of attention to Adamantine, as it had been pivotal during the Convention. Who knows?