This isn't me. But there is Paul Erdős, who made great contributions to mathematics. He was known to use amphetamines regularly. He even made a bet with one of his colleagues on his amphetamine use, betting that he could give up amphetamines for a month. In which he ended up subsequently winning but complained that mathematics was set back by one month.
Yes, Paul Erdős apparently was capable of using amphetamines without excess. I don't know how someone would know whether they could prove capable of doing the same.
Also, at the start of World War II the German soldiers took amphetamines. Accounts of the invasion of France describe some unusually daring/reckless and physically daunting tasks that likely, w/o amphetamines, would not have been done. Staying awake for days seemed to be part of the job:
