Even if the semantics of CAA were changed, the challenges described in paragraph 3 of this post would apply: https://www.imperialviolet.org/2015/01/17/notdane.html
could we change this? Ie. if the CAA record disappears, it would be a reason to revoke a certificate?
Then 3rd parties could scan transparency logs and CAA records and flag discrepancies.
Personally I think this is another good argument for short lived certificates and reducing reliance on revocation systems.
Even if the semantics of CAA were changed, the challenges described in paragraph 3 of this post would apply: https://www.imperialviolet.org/2015/01/17/notdane.html