1. The likely doses prescribed, added with the fact that tolerance to amphetamines develops quickly, means there is no likely scenario where "2 or 3 year-olds [are] legally high on amphetamines everyday[.]"

2. To the article's question, I am not all surprised since in this society people are prescribed Adderall en masse for ADHD and broad attention-span or motivational problems. Keep in mind that Adderall is a combination l-amphetamine (what you find in UK street speed) and dextroamphetamine (which is structurally similar to the properties of meth -- that's not to demonize it though; people are generally misinformed about meth.) They are not only prescribed to take it everyday, and /might/ face long-term effects based on the fact that they're stressing their dopamine receptors constantly since the brain has to oxidize the excess dopamine that is being released everyday -- though tolerance mitigates this -- but they are seriously told by psychiatrists that they cannot get addicted to it if they have ADHD. Yeah, right.

3. Ritalin is not an amphetamine.

4. "Just imagine how badly a human being would be messed up if they did amphetamines starting at age 2." It depends on frequency of use, dose, habits such as a proper nutritional intake and hygiene, etc. Even if it is used everyday with a dose that isn't increased by much or remains stagnant, and they don't replicate the bad nutritional habits of the stereotypical amphetamine addict, then given the resistant effects of tolerance they shouldn't come out too bad. And we really don't know that much about the long-term effects of its use, or about the recovery periods from it.