Hm. SO does this new “parentOffsetMatrix” now make it unnecessary to create extra Transform nodes for all of your rig control curves? Meaning you can set your control translation/rotations to 0 to reset them to reference/base pose without needing to “group” your control curve under a parent Transform?
Update 2020.1 is ready.
Maya_USD does have a binary download.
Arnold is also able to load USD files as standin.
MaterialX is now on v1.37