Blender 2.8 Animation, Bake Action, is it broken? This question was asked Here but not answered satisfyingly.

I am attaching sample files where I reproduced the issue:

Repro:
Using Blender 2.81 (but seems to be broken in all 2.8x releases)


shift+A and drop an armature or bone.
translate object around creating a few keys down the timeline
in NLA editor make keys into a strip
in a new track create more keys down the timeline
make these into antoher strip so that you have a stack of two strips on two
tracks.
Now go to Pose > animation > Bake Action.


Expecting: Baked
    down track to result in the combined animation of both source
    tracks. Instead it acts weird, if you hide the two source tracks and
    only play your baked action you'll see it's not right.

2 Sample files are here


The Rigify file, seems to bake a key on every frame. But if I turn off the base tracks to only play the resulting combined track, you'll see the character just pops back and in the end even disappears somewhere instead of simply returning to origin.
In the other file I tried it again with a base joint rig, not controls. Same result except this time for me the Bake Action command only bakes the first and last frame even though I have it setup to bake every frame.


https://drive.google.com/open?id=1LKUqg_rmoZAn25UAUul1p6LX_0ANBLnm

Is this broken or am I missing something ?
After tinkering with this here's how I work with Baking Actions:
Once you have all your edits layered as NLA tracks and you are ready to bake down to one replace layer:
Make sure that the New layers under the Animation Data tab on the right of NLA editor is set to Replace.
In pose mode, Select all the Controls of our rig, or all bones.
go to Pose > Animation >Bake Action.
In the settings use "Selected Controls" it is way faster.
Also make sure Visual Keying is on
Remove constraints if you are trying to bake animation onto a constrained object. otherwise you can leave it checked off.
When you run the Bake Action script you should get a flattened replace track of your baked animation.
If you are having issues with this, feel free to ask for clarification !