I know everyone sees them on racing cars, especially Formula One, where it's evolved into a science and artform......
....but in reality 'low-speed' [that's what it is] aerodynamics will show they are as beneficial as the proverbial 'tits-on-a-bull' at anything RESEMBLING a legal speed limit.
Yes, an F1 develops enough downforce at 120mph to drive upside-down on a ceiling....[which is totally impractical], and even the road car I drive has a rear 'spoiler' added because designers discovered the car wanted to 'wander' at speeds around 130-odd.
OK, so they look 'groovy'....like Starsky and Hutch's 'stripes'....but really....
The issue is with people who insist on SPOILING other people's enjoyment of a film or TV series, etc.... why?....to show off that they have seen it already...or what?
Here's a hint.
It's called a "spoiler" FOR A REASON!
What say you learn communication skills which enable you to talk ABOUT a movie WITHOUT ruining it for anyone else, OK?
It's actually NOT THAT HARD.
And no, alerts are meaningless....and about as useful [usually] as warning someone you are about to shoot with..."this might hurt".
Remember the movie with the line "I see dead people"? Imagine how that can be SPOILED.
Saying [about Titanic]..."oh, the boat sinks in the end..." isn't quite the same thing....and that's where common sense kicks in....along with consideration for others.