My take: Müller's system combined with yoga and meditation might be the perfect exercise system.
From the article:
The exercise guide, which promised that just "15 minutes a day" of prescribed* exercise would make "weaklings" into strong men (and women)
Müller wasn't interested in building muscle mass through dumbbells.
Source: Franz Kafka, J.P. Müller: The exercise system that swept Europe in the early 1900s. (Sarah Wildman - Slate Magazine)