grwoolf -

I think you're doing fine too. It seems like you're taking a structured approach to your cycling. Since I can relate to that (although I am not a structured traing kind of guy), I'd experiment with the variables and note the effects. Write stuff down in a training diary, even if it's basic stuff (like "rode really easy 15 mi").

The thing on drinking before thirsty etc is a often repeated bit of advice for anyone on longer rides. Your body doesn't send hydration and energy alarms until it's too late/ By the time you're thirsty, you're already dehydrated. ditto hunger. So the normal thing to do is to sip before thirst and eat before hunger. Foof is usually not an issue until you start depleting you "on board" reserves. That typically lasts 2 hours or so. If you're riding longer, you need to eat, shorter you prob don't.

I find that eating "a bar" every hour works for me. "A bar" usually means a typical energy bar, not a lowfat one (watch out for maltitol, used in "lowcarb" bars - it's a strong laxative - and yes I found out the hard way).

For fluids I usually carry a bootle each water and gatorade type stuff, replenish as I use them

For rest, yo may find that an easy spin Fri will give you freer spinning legs on Sat.Try and see. Most "serious" riders need a day on the bike (after a rest day or two) to feel good on the bike.

hope this helps
cdr