'Bent designs are still evolving. The climbing performance of a select few (e.g. MetaBikes MetaPhysic and the carbon high racers offered by Carbent and Bacchetta), is starting to rival that of uprights while still keeping a considerable aero advantage for the flats. It's worth noting that it takes some time for your body to train to the specific way in which your muscles are taxed on a ben compared to an upright; that competitive climbing performance phenomenon is not experienced immediately. I believe some will always find uprights to still be faster up hills, even after training. It may depend partly on individual physical differences and riding style differences.

Stretch the time scales, and comfort advantages start to play a role in speed. A comfortable cyclist is a faster cyclist. And sometimes in ultra races and brevets, 'bents keep the riders on the bike more consistantly too. Seems like some folks dilly dally at stops because they dread getting back on the bike, and the clock doesn't stop ticking because you needed to stop to put cream on your nether regions and change shorts.

Ultimately though, you already seem to realize that there is no one right answer. 'Horses for courses', and all that. There is nothing wrong with riding both and choosing the machine you prefer based on the day's course, whether or not its in a group or solo, the length of the ride, etc.