Not easily, from memory, but I'm not thinking in terms of any Golden Age material (of which I have lots), but of more modern stuff (not originally written as tango music). It meanders off with no 'pattern' to the pulse when you can hear one, and while others can dance to it, I have yet to acquire the knack.
I have a friend who plays such stuff all the time, and she keeps offering me copies, which I politely decline ...
I just haven't noticed that vals is danced to such material - but as I say, it is the form I least familiar with.
Maybe I'm misunderstanding your point. If so, my response won't really address it...
Vals is
defined by having a waltz tempo time signature. It isn't really defined by having specific
steps that differ from tango. The steps (or patterns) used in waltz are all used in tango as well (but the reverse is where the problems come in)
On the other hand, "Tango" (in North America anyway) is defined by dancing
in a tango style to whatever music is playing (as long as it isn't milonga or vals) So "tango music" can have all kinds of different tempos, styles, instrumentations, orchestrations, etc. It can be pretty much anything from traditional Golden age tango music, to Gotan, to some other popular music (or obscure music) that the DJ found and decided to give a whirl.
Basically, when music comes on at a milonga, people figure out whether it is
A) Tango
B) Milonga
C) Vals or
D) a
break from Argentine Tango to do a Latin, Swing or ballroom dance (in which case, people who don't know that dance sit out)
So everything that gets played is analyzed first by the "AT or not AT" filter and unless it CLEARLY falls into the "not AT" category because it is some other
specific dance, it is placed into A,B, or C.
Since B and C are defined more rigidly,
everything else goes into A: Tango.
It's the big paradox of how AT is morphing (and what upsets the purists) "Tango" means dancing
movement that is part of the overall AT family of styles (be it neo, nuevo, V, milonguero etc) to whatever music is played. However, even in the AT world, vals is defined by the
tempo of the music being a waltz time signature.
So "tango" is defined by how you are moving regardless of the music and "vals" is defined by the time signature of the music.
And that may be why so few tango leaders I know can express vals any differently from tango. They hear that it is a different tempo and say "Oh it's a vals", but they just
dance it the same way they would any other "tango". Since they already do "tango" to a wide variety of music, waltz tempo is just another piece of music they "tango" to. For someone who has danced waltz tempo outside of the AT world, it doesn't feel right... it doesn't feel like WALTZING. (usually because it lacks flow)