In my previous review, I mentioned that the text about graph theory seemed to make the document harder, not easier, to understand. This was an editorial comment, which the authors mostly ignored, which is fine. They did add an admonition to the reader to read RFC8499 for further clarification, for what that's worth.

I also mentioned that the diagrams that show the ACME process aren't contextualized as being part of ACME, which made it hard to figure out where these operations were actually described in a standard.  The authors added some text that may have been intended to address this concern, but it's not clear, and I don't think this suggestion has been addressed. It was an editorial nit, so that seems like a reasonable, if disappointing, reaction.

I also mentioned that the text about the use of ACME for subdomains is somewhat contradictory, since in one place it says they are not necessary, and in another case it gives an example that depends on them. Some text has been added that may have been intended to ameliorate this concern. This was a "ready with issues" point, meaning that I thought it should definitely be corrected. I think this change addresses the concern.

I also asked for a clarification in the security considerations section (now section 10) that the mention of using DNS updates and TSIG or SIG(0) was needlessly prescriptive. The update softens this text and I think addresses my concern.

I also pointed out an issue with the text implying that TSIG uses "DNS key records," which it does not, and the new text no longer confuses key records (SIG(0)) and TSIG keys, referring to both as "credentials." This addresses my concern, and also includes other means of update in the concern about credential leakage. I think this addresses my concern.

I further requested that references be given for RFC2136 and RFC2931 since the mechanisms described therein were being referenced. These references have been added.

So I would say at this point that the concerns I raised have been addressed and the document is ready to go.