What to drink during training rides

You can't process enough during a ride to maintain glycogen levels. Even if you take in various forms of carbs, which is the best way to maximize absorption, you most likely can't process enough during a hard training ride. That said I take a portion of my calories through fluids, but I still need to restore levels afterwards.

I haven't heard it recommended to take in carbs after a ride instead of during a ride. What I have heard is that sport drink is is not necessary during low stress rides, presumably because there is not very much glycogen depletion. I assumed that meant that you didn't need carbs after such rides either.

Personally, I tend to drink just water during my weekday 1 hour commute/workouts and drink a recovery drink afterwards. However this is more of a laziness thing. I avoid having to mix the sport drink before the ride and clean water bottle afterwards. I drink the recovery drink because it tastes good after a ride and I figure it's the best time to indulge in a chocolate milk or fruit smoothie.

I drink High 5 isotonic during training rides to replace fluids, salts (which water won't give you and aids fluid absorption) and some carbs, and supplement with flapjack or similar to replace carbs. After the ride I finish off whatevers in the bottles and then eat/drink normal food/drink.

Got 2x750ml bottles on the bike, and just ordered 1000ml bottles for even more fluid for longer rides.

I'm not sure what you mean by a "cordial" type drink, but for rides of 1-2 hours energy drinks aren't necessary for a large number of riders. Drinking water might get some people by, but others will or might do better drinking electrolyte replacement fluids during such a ride. The popular electrolyte replacement drinks, now, are those fizzy drinks that riders can make just by dropping tablet or two of the electrolyte replacement in their water bottle. Nuun, Camelbak, Gu, Hammer, and many other companies make such drinks. A very nice aspect of such drinks is that they are not sweet and come with a comparatively mild taste (when the comparison is made with energy drinks). I use 'em on all rides. For rides up to two hours, that's all I'll consume. For rides longer than 2 hours, I'll drink the electrolyte replacement drink as well as an energy drink.

If it is hot I tend to drink fluids with electrolytes. I can lose 4-5 lbs even when hydrating in very hot weather.