If small sugary drinks at right times work

You haven't yet sufficiently defined what "work" means. Scientists have had trouble replicating some ego depletion experiments in humans, and there appear to be confounding factors introduced by the fact that it's the experimenters choosing the tasks, and the fact that the subjects are already motivated to co-operate.

This is almost nothing like the environment for individuals' personal/private akrasia.

That being said, I would be happy to be proven wrong. Feel free to go try it for a month, then come back and add it to the anti-akrasia techniques survey results.