Last summer my friend was wearing a new, very expensive Assos matching pair of shorts and tank top. They had been a birthday present from her husband, the previous winter.
Usually, I am leading when we ride, but a very bad thunderstorm was threatening, so she got her butt in gear and started to pull. I was in shock when I realized that I could see through the entire top part of her shorts, skin and crack area. I knew they were brand new, but they were made of that material that is sort of vented for cooling air flow. I have one pair of Shebeest shorts that have the same thing, but in a smaller area, just above the crack area.
I had to tell her. I don't think you could see this if you looked at it yourself, off of your body. Most disturbing!