I've sort of noticed a trend about the timelines that are unusually bad is that they're just so long and thorough.
Queen Nixon, for example, is >1200 book-length pages long.
I mean, one thing that makes unusually bad TLs unusually bad is their sheer length. It means that they take their fundamentally unsound premises to bizarre directions. It meant that Queen Nixon went from “Eisenhower passed the Voting Rights Act with no backlash whatsoever” to “Queen Nixon” to “Mandela supports apartheid”.