Right. And using "which" that way totally works, too. However, it is a word that is used more often when spoken, than in writing. "Which might explain..." is something you would speak out loud. Or write in a script. But due to the multiple meanings and usages of "which", when writing for clarity you would want to rewrite the sentence to eliminate the use of the word completely. The Tesla example you give is a case in point: It just isn't a well-written sentence. It's ok, sure. But not well written. The point is unclear, it's a half-thought, not a complete sentence, and the subject (the point you were trying to make) is buried at the end of the sentence. If I were a copyediting your work, I would encourage you to rewrite the entire thought, which would include this sentence, and probably the two prior to it as well. (See how I snuck "which" in there? :-) "The point I made earlier was that the transportation authorities do not prevent Tesla from driving in automatic mode." Now you have a complete sentence, with an obvious subject, position, and assertion, and have eliminated probably two other sentences around it. Can you tell I kinda love copyediting? :-) I'm a total geek for this kind of shit. Just ignore me... I'm entertaining myself here... :-)