I know this is typically frowned upon, but what if I were to lift, drink half my PWO, then do a quick 20 minute HIIT, and immediately finish the second half of my PWO?

Would that allow me to get the effect of HIIT, before the PWO actually digests into my body? I heard this somewhere, and I was just wondering your guys thoughts.

It's not just a question of the effect your food will have on your cardio, but on the effect your weights and cardio will have on each other. It's widely accepted that your body has a defined "window of effort," in which it can be pushed hard. Doing cardio too close to weight training can hamper your efforts in the gym, or vice versa.

It's not really all that difficult to schedule them at different points in the day. Cardio is generally more effective for weight loss when done fasted in the morning anyways. I just get up and do my cardio and then do my weights when I get home from work, which gives me a good ten or so hours in between to recuperate.