I have no time to read the topic so this may have been said already, but I felt the need to say this:
When talking about concentration, the Buddha was talking about a specific kind of concentration. Not the kind of concentration one uses in everyday life, but concentration based on virtue, contentment, peace. Concentration is not really the right word to describe it because people don't always know about this distinctive type of meditative states the Buddha was talking about and mix it up with general concentration. So the concentration we try to develop is not supported by drug intake.
Same for energy. It's not just any kind of energy that's good, we have to be careful there. Cafeine for example may give energy but it is not a very stable kind; it's very wobbly. Therefor it's not particularly useful and it is certainly not the type of energy the Buddha was on about. That would be the energy more based upon joy.