David, a "lossy" design is thin-walled, designed to resonate at an unobjectionable (usually higher) frequency, rather than a thick and rigid cabinet which will resonate no matter what you do, sometimes at an unintended and objectionable frequency. If the cabinet is designed to flex anyway, there is not much point to having a super-rigid stand.
BTW, I sold my P3s and have a surplus set of TR70 stands if you know anyone in SoCal who might need them.
