In my blender, constant detail adjust bar show up with 'resolution : ' unlike yours.
I follow up your instruction but i found that my blender is not like yours.
When I setting up dyntopo options with Subdivide Collapse, Constant Detail. but then [Resolution : x.xx] is appear on adjust bar.
but in video, adjust bar show up like [Detail Size : x.xx %] even i choose same options(subdivide collapse and constant detail)
how can i fix this? I want to adjust my brush scale with Detail Size(%) like your instruction but my blender can't show that "Detail Size"
my blender ver is 2.79