They don't necessarily agree with each other, though, so I'm not so sure how "authoritative" individual blog comments are (see e.g. Bradfield's followup to Jutl

They don't necessarily agree with each other, though, so I'm not so sure how "authoritative" individual blog comments are (see e.g. Bradfield's followup to Jutla -- "And I don’t understand your comment about it not being known whether mu-calculus has a hierarchy of expressibility in alternation. It’s 15 years since I (and independently Lenzi) proved that it did!")