You can get a similar effect by setting the oil brush to 0% loading and 0% thinner (and I usually turn stiffness all the way up), and stroking over existing oil on the canvas. However, this is very limited because even with very thick oil on the canvas, the dry oil brush does not carry the oil like you would expect from thick, wet oil, so your blending is very limited. Using the dry brush tends to quickly "dry out" the oil and flatten it into the canvas, making it so you can't rework the paint after the first couple strokes with a dry brush.
I do wish that there was a dry brush blender that worked more like a blending knife but with the dry bristle look.
*Edit*
I just saw these blending types linked in another page:
http://artrageteam.deviantart.com/ar...Rage-578063151
http://artrageteam.deviantart.com/ar...Rage-578065795
They don't address the things I would like to see improved about the dry-brush blending, but there certainly are more combinations for blending than I knew of.