Talk to your doctor(s)! The following is what it is for me, and may not at all be what it should be for you!

I'm type II diabetic and I've dealt with the same issues. Neither the PCP, a rider by the way, nor the endocrinologist had any concerns about my eating during rides.

As for the "don't head for the shower, head for the fridge" advice in order to speed recovery upon return including the eating high glycemic food (fruit, for example), the PCP was more worried about my blood sugar being too low. But both had an empiricist attitude towards it. Try it, check your levels and see what they are. I did this on a number of occasions after eating upon ride's return, and my numbers were completely normal. I took my measurements a more aggressive 1.5 hours after eating, not 2 hrs as is often used.

But again, talk to your doctors.