Yes your experience with the Seismic Pods, de-coupled the speakers from the suspended floor. As does Herbie's Titanium Cone/Spike Decoupling Glider.
When I isolate (de-couple) my massive Martin Logan Monoliths from my suspended floor, the bass becomes far tighter faster and deeper and without overhang, and the image is improved.
If I couple them into the floor with spikes, then the bass becomes one note'ish the floor vibrates through your feet, and the image is also shot to hell.
Cheers George