Yea the speed of charging depends on thickness and a thicker cable charges faster and has less drop in voltage while conducting which results in better charging. I'm not going to do a Physics lecture with you, but thin cables are not better than thick cables!
Think whatever you want, but I find it quite rude that u keep on saying it's all in my head... .
I'm not the only one who got better results with a thick cable!!
The quality of the charging cable has nothing to do with how many milliamp hours the battery has when its physically full. No matter what type of cable you use to achieve the 100% physically full battery cells, they do not hold a greater charge depending on the physical properties of the cable used to charge it. This simply is not magic. If you think it is, refer to my comment using your logic in reference to a cars fuel tank. If that still seems to logical to you, then no matter what any one says, it's futile. And you can believe what ever you like to believe. But logically your theory is flawed, and this is how wives tales start in regards to devices.
If you think my self saying it's in your head, because it literally is, is not needed. Look up the placebo effect. If you're offended by it, all i can say is some times the truth is unsavory (in the eye of the beholder, this is relative, of course) but its still the truth.