Basically, that would be the same as adding an air-gap on the countertop. Problem with air-gaps was that they clogged up and caused more problems than they solved. This is why many areas reversed the code on installing them. Are you tying into the sink drain line or disposer? I would suggest simply running a loop as high as possible under the countertop (as suggested in most DW installations) and see if that works for you.
If you have never made a mistake, you haven't done much.