It is actually possible to prescribe meth, although it is rarely done anymore. The brand name is Desoxyn, and it can be prescribed in 5-10 mg doses for ADHD and a couple of other indications.If there is scholarly work being done with meth as a useful drug then great. Should it gain FDA approval (if it hasn't) it should be prescribed and taken as directed.
What we see in my state on the ground is near total brake down of communities affected by meth addiction. It's a mess.
The main issue with meth isn't so much that methamphetamine specifically is particularly dangerous. The problem is that illegal meth users consume extremely high doses, by dangerous methods (smoking, snorting, or injecting, instead of oral use). The underground manufacture of meth also often causes poisonings and explosions. But when meth is prescribed and taken like amphetamine, its effects are similar to Adderall.