no i have tried, even one iteration of blur (the default was 14 or 16 i think) causes lag. its the same with drop down menus, set blur to zero and they are really smoothe, but look a bit crap without the background blurred out.
also a good effect is editing zoom


[home]
radius=6
radius_more=0
saturation=0.8
brightness=0.6
zoom=1 <--------------------------------------------
zoom_applets=075

makes each level of the ui zoom in a little, or alot more