We had a discussion over on Gearslutz about this, because the coupling/decoupling terminology and when to apply it tends to get really confused in most discussions.
After some research and Ethan Winer chipping in, we basically deduced it to this:
If you have a good, solid speaker enclosure (high mass, low resonance), then what you want to do is decouple that enclosure from the environment, to not transmit frequencies through solid surfaces. MoPads sort of do the job here, though purpose built stands tend to be more effective, especially if there are multiple points of decoupling.
If your speaker enclosure is low mass and vibrates fairly easily, well then you're after something with high mass to couple to your speaker. This would include 1) a good, solid, heavy speaker stand and 2) Something like the Primacoustic Recoil Stabilizers. You basically just want something heavy to couple its mass to your speakers. Some people use sandbags, others cinderblocks etc. MoPads are no help here.
The ASP8s are the heaviest and largest monitors I've ever had. That inspires confidence as to their enclosures' self-damping properties. As a result they sit on little rubber feet on the base plate of the stands, and the stands themselves are filled with sand (to not vibrate sympathetically with the speakers), and stood on carpet spikes (to stabilize them, and prevent rocking, or back and forth motions which could lead to frequency cancellations).