I think you're both right but let's set this straight…
Under anaerobic conditions only glycolysis is able to produce ATP.
After a glucose molecule goes through glycolysis we are left with 2 pyruvates.
The pyruvates accept electrons from NADH allowing it to be oxidized back to NAD+ and reused in glycolysis.
After accepting electrons the 2 pyruvates become 2 lactate molecules.
The lactate can be converted back into pyruvate by the liver.
So…
No energy is directly formed by lactate/pyruvate, however without these molecules NADH could not be used again and the ATP yield from glycolysis would decrease.
Back on the original topic…
Remember that more diluted does not mean better absorption, this is why sports drinks like gatorade/powerade are kept around 6-7% concentration.
It is debatable whether 2 drinks is really better than one.
One argument for 2 drinks would be that glycogen is better replenished by smaller and more frequent CHO intake PWO, saw a study on this a while back.
An argument for 1 drink perhaps would be that the insulin 'surge' would be greater.
I am not a big fan of high sugar drinks and cranking up insulin all the time.