Originally Posted by Fabrik8

And you've drank the Kool-Aid but probably can't explain the reasons behind that debate.

I understand all of the engineering theory behind why they shouldn't work, but I've seen them have visible benefits and that's the point that is hard to argue with. I will agree that they won't do anything for the sound system or how well it performs, but they do sometimes help with headlight and dash dimming.
Do caps work anywhere near as well as what their marketing says? Absolutely not. No debate there.

A bigger alternator is definitely the better solution though, because nothing can help you if you are drawing more average current than what the electrical system can output. If you play bass heavy music, hip hop, etc., and you have headlight problems, a cap is not going to do anything for you.

So although I agree with what you're saying, I still recommend that people try them when trying to solve minor annoyance problems like quick headlight or dash dimming.