Bonking in the usage I have seen it is glycogen depletion. Once you glycogen reserves are gone, your body has to burn fat. Fat takes twice as much oxygen to liberate the same amount of ATP, that is chemical energy, as glycogen. I understand one can delay glycogen depletion but not stop it by eating during the ride. It seems to be true from my experience which is not backed by chemical analysis.
Now one would think that slowing down a bit would delay the depletion. The reason for this is you are being fueled more by fat burning than glycogen which would save the glycogen. With very intense riding, one burns almost 100 percent glycogen. If you push hard, you are going to pay for it on a long ride.
Now with headwinds, I find it hard to back off as much as I should. I can back off on hill climbs but it seems to take far more discipline to back off with headwinds.