on unstructured tinkering and statistical validity…

• https://en.wikipedia.org/wiki/Quasi-experiment
• https://en.wikipedia.org/wiki/Natural_experiment
• https://en.wikipedia.org/wiki/Design_of_experiments
• https://en.wikipedia.org/wiki/Concept_development_and_experimentation

demonstration vs. experiment

• A demonstration is a way to explain a principle by an example. it provides evidence of the the principle under investigation.
• An experiment is a test performed to discover an unknown or to validate (or refute) a theoretical principle.