The comment I replied to said that the various ways this technology/regulation could have harmful effects were theoretical "what if" scenarios. I pointed out that the ways it could have beneficial effects are also theoretical "what if" scenarios. I'm not saying that people dying because of drunk driving is "what if", I'm saying that this technology/regulation preventing drunk driving is just as much of a "what if" as it doing anything else. Just because something is advertised as having certain effects by its proponents doesn't mean it actually has those effects.