First of all, I'd like to point out that the robot pictured is Chief Delphi's, not HOT's. It says so on the side
I think wedges are a valid design, but gracious professionalism has to go hand-in-hand. If you are an aggressive wedge you're going to be called on penalties. I see it like basketball; you're not allowed to shove someone, but if they run into you it's their problem. In that manner, a defensive wedge would be perfectly legal.
A wedge with another, non-offensive or defensive use would be perfect (Wildstang in 2001, wedge-to-ramp).