Fleece warmer than High Loft?

no

I think that depends on how you define fleece.
I have an old TNF jacket made with Polartec 1000, which is no longer made [ it’s like 2 layers of 300 laminated together] and it is very warm, but also very stiff and heavy.
If the term “fleece” is broadened to include “pile” then there are many products warmer but again with a weight penalty.
Perhaps ThermalPro offers the best combination of weight Vs warmth tho.

This thread led me to visit Polartec.com where I noticed a fabric I had never seen, Power Air.  No idea where it fits in the warmth spectrum, but interesting that Polartec is attempting to address the shedding in plastic fabrics.  Or is this just marketing spin?

Alpha Direct is the warmest/weight fleece.  It’s basically High Loft with a looser weave so basically the same.

Paul is right with Alpha direct.

This thread led me to visit Polartec.com where I noticed a fabric I had never seen, Power Air.  No idea where it fits in the warmth spectrum, but interesting that Polartec is attempting to address the shedding in plastic fabrics.  Or is this just marketing spin?

Its definetly on the heavier side. I have “light warmth” power air lying around. It feels as heavy or heavier than classic 200 fleece for much less warmth. I believe it is an attempt at creating a more durable, less shedding, gridded fleece equivalent (warmthwise), but with a weight penality.

All in all, definetely on the low end of the warmth spectrum

Did you see the fleece article by Stephen Seeber on the homepage? Variety of fleeces, including Thermal Pro and Alpha tested.