Going for Assembly Line just feels too much of an exploit for my sensitive self. Getting a 20th century tech without researching any of the 16th century ones before just wouldn't feel right, how convenient as it would be.
Navarre,
Have you ever played with the tech tree from turn zero? You can get all sorts of wacky stuff without training for some key techs. For example, you can research Assembly Line without getting Hunting, Aesthetics, and Iron Working.
Machinery doesn't require Masonry.
Replaceable Parts doesn't require Iron Working, Construction or Engineering.
Astronomy Doesn't require Engineering nor the Knowledge of Construction.
Corporation doesn't require Alphabet.
Biology doesn't require Agriculture.
Heck, you can get Future Tech without knowing about Fusion, Computers*, Literature, or Agriculture!
*We all know the ongoing gag about how you can launch a spaceship without the knowledge of computers, too.
You can do a lot of silly things with the tech tree. Unlike worker city capturing, this seems like it was very much intended and not something of a bug or exploit. Yes, they seem silly, but exploitative? Naw.