There are several interpretations of what "double weighted" means. The one that makes most sense to me is this:
Double weighted is a state where the balance of a person is broken in such a way that the person cannot move effectively without taking a step (a fraction of the body is supporting all the bodyweight, so it's supporting "twice" the load it would naturally hold).
You may find this interesting:
The positions in your videos don't look double weighted to me.
"
Investigating the matter, we find that any time we use strength — which is every time we try to move a heavy object, struggle with a significant force, or meet with some resistance to our actions — we always brace up. We also tend to lean our body’s weight in order to counter any weight or resistance we run into.
Simply observe any “push hands” competition and you will see these activities obviously taking place. If you study this, you’ll find that whenever people try to apply or receive a force, they always use strength, brace up, and lean. Further investigation reveals why."
Use the term in my practice....to mean
Mind and body at the same point "full" = double weight
Mind and body both not at the same point "empty" = double empty"