Fair enough.  It moves the entire set of CTs into a data structure.  Old clients just verify the total of the confidential transaction outputs.

It is a complex soft fork like segregated witness which adds additional data structures to the blockchain.

Since the "nuclear option" can completely replace the rules with another set of rules, "soft fork" can mean a very extensive change, depending on where you place the line.


Something weird must have happened to the forum's search feature.  "Confidential transactions" was not hitting that thread.