I'd think for any cardio/aerobic activity such as cycling, then empty Calories by themselves are okay. You aren't expressly concerned with overall nutrition while you are riding as much as you just want to provide foods and drink to your body that will carry the things you need to help replete spent energy.
As for cornstarch, I'm not gonna try it... maybe Mikey will eat it. (at least not for cycling fuel, when so many other things are around).