Heya,
no, the filtered view via middle mouse click did display a different set of columns, and the ones that it did share with the main tracks based library view they were in a rather different order. i.e. in all my saved 'custom views', on I have:
Artist | Title | Time | Track # | Album
The view it was presenting me with was beginning with 'album' set as the first column. But, it also had, IF/when middle clicked, a 'note' column as the very first.
After playing with this some more after posting this, turns out IF you apply a previously saved 'Custom View' to the middle-click-opened view once, this will stick and will be used on all future middle-click views as well.
So this is solved / fixed now.
Cheers.
c.