What do your 400 cal/hour consist of? List the duration if your last ride where you had the blackout and the fuel you consumed on that ride.
Did you pace that ride by power or heart rate? Please provide some ride data that shows what intensity you were riding at during each hour of the ride.
Did you have any stomach discomfort or bloating on that blackout ride.
You can blackout on rides if you are over-trained and completely smoked too? Is that a probably answer?
Lynda