If you look at the FULL design, it's actually pretty good - things like https://en.wikipedia.org/wiki/Certificate_revocation_list CLRs have actual thought behind it - but I know of no system that actually IMPLEMENTS everything, for various practical reasons.
So from a spherical cow perspective, it's well-designed; from a "this has to work in the real world with real things and people" it's ... workable by violation of the design all the time.
So from a spherical cow perspective, it's well-designed; from a "this has to work in the real world with real things and people" it's ... workable by violation of the design all the time.