I learned about carbon steerers and most clamping systems on stems and seatposts a while ago, I don't remember the context but I thought it was interesting.

Apparently symmetrical clamping systems like you find on many stems and seatpost collars can cause undue pressure on a localized point of the carbon tube, leading to premature catastrophic failure. Asymmetrical systems spread the load over a greater surface area, preventing fatigue of the carbon parts. That's likely why Dimension recommended not to use their stems on carbon steer tubes. Stems with sections cut out between pinch points can also cause a failure due to point load.

Here's one explanation of the phenomenon. Also, I am RIPPED right now, hope this came across coherently.