dogsbylori

1. yes
2. yes, but instead of hsl you could select "black and white" (it allows you to better tune the bw result)
3. yes
4. yes, it works, but imho a better option would be:
    4.1 select the duplicated image
    4.2 go to menus, Layer => New Live Filter Layer => Gaussian Blur
    4.3 slide the radius till you get the effect you're looking for
5. yes
6. optional: select the duplicated image go to adjustments > Recolour and set the hue as desired if you want a colored image instead of a b/w one
 
now the question about "live filter".
yes, i did mean what you show in the image you attached.
the advantage of using live filter layers (instead of the filters that you can find in the Filters menu) is that live filters automatically set the effect as a mask you can edit later, just like adjustments:
- if you later double click on the mask, you reopen the filter's controls and can modify all of the settings
- if you later click on the mask, you can paint over it with the paint brush. note that the effect mask is white by default, which means that the effect is shown everywhere: so you'll paint black where you want to hide the effect. you can invert the mask (click on it and then press cmd-i): this will hide the effect everywhere and you'll paint white where you want the effect to be shown
 
in other words, live filter layers allow to edit the image non destructively. you can modify the filter's settings, delete or deactivate it, mask it, and so on, without the need of throwing away the editing work you have possibly done after setting the live filter.
on the other hand, the filters you apply through the Filters menu are destructive: they modify the pixel structure/color of the image. you can undo them, but if you do more editing after applying one of them and you want to undo that filter, you'll have to undo any subsequent work and redo it again after applying your changes.