I tried some of that carb+electrolyte chemical stuff for the 3 hour endurance race at Betteshanger. It tasted disgusting and given the state my digestive system was in afterwards, I'd have been better off with plain water. On the other hand, I didn't bonk after the second hour, which is what I expected to happen. On the gripping hand, track racing isn't audax.
The lesson here is that you need to experiment to find out what works. Preferably when it doesn't matter, rather than during the world championships.