I'll concede that if you're a speedy young whippet (which I'm not) then nutrition might have some importance because you may lack the natural fat reserves that us regular mortals possess. After my usual breakfast (home made cereal and toast) I wouldn't normally bother to eat until I get back home on a ride of less than 6 hours. (OK, I do do cake occasionally - I can handle it.)
Oh, I take food with me - I've been carrying the same flapjack around with me since I got it from the NEC bike show last September, I just can't bring myself to actually eat it. Same goes for gels and energy bars, they taste disgusting but they have a purpose, they're there to remind you that you can manage at least another 10 miles without having to eat anything, and 10 miles on they're still there to remind you that you can do another 10. And so on until you get home. Most of mine are past their sell by dates but they still work. I'm sure it's where Terry Pratchett came up with his idea for Dwarf bread - something so horrible that you'll always find something else to eat. Like the soles of your shoes.
And, for extra insurance, a bottle of cider chilling in the fridge works like magic. I can hear it calling to me as soon as I turn for home...