Velcro as Acoustic Isolation?

Velcro dissipating energy as heet?

That concept is laughable.

OP I understand, most thing do dissipate energy as HEAT. Interesting, but again, I think it is dissipated by simple surfaces on the cabinets. 
A little different than you're thinking. It is measurable decay rate. Some go to great lengths to control that. The shorter the panels, and tighter bracing, the quicker the decay rate. That is what we want.  The inside of cabinets treated with sound coat, actually work on that principal.  Vibration is converted to heat, the cabinets work better, with a port and proper COOL air to keep the drivers at a given working temp..

The batting is another, place DIY and a lot of manufactures fall far short.. The batting in those cabinets, take a good long look at that alone. Three years I tinkered with liners, lining and  batting. From highland wool to heavy insulations. I put it in bags, with different, thread counts to multi layer bags. Nitrogen filled bags.  I tried all kinds of stuff.  Wool for the mids, HEAVY fiberglass for the subs and a lighter batting like poly fill for the MB.

One batting does not work for all, AT ALL, on everything correctly..
Like the Tinkers Titin says "for peanuts", compared to what we do outside the box..

Sometimes we do have to think INSIDE the box, not outside...:-)

Happy hunting.. good ideas only happen if you try.. Nothing wrong with that...

Regards

slaw friction...