This is a great idea, to make grooves I often had to take a few steps, but with this one... in just one step.
But, Sketchup sometimes freezes with this one installed, but when not, it certainly messes with Fredo's Lord of the Toolbars all the time... so I had to disable it (rename the extension, because it does not stay disabled.
P.S.: All DBUR extensions I've tried (and use) so far do not run from a folder other than the native one (except Align_2D_3D and Align_2D).
For this thing I use TT Extension Sources, which is in fact the only true Extension Manager that Sketchup has; the native one is just a shame.