Not wrong at all. All you can "prove" experimentally is that something is more likely to be true than false based on available evidence. At no point is anything proven to be true (or false for that matter). If you really want to keep going we can start digging in to how easily your "proof" can be skewed by poor experimental design or sample bias.
Or we could agree to disagree on our definitions of proof?
yes that is true. However if you want to prove that gravity exists would dropping a ball at a height not demonstrate the effect of gravity and hence prove that it exists. It wont however EXPLAIN why it exists or detail gravity itself. So from that you can say gravity is an attraction of two masses this is the law of gravity and its FACT and was proven fact by simple observation. It was later detailed using mathematics and extended into warp of space-time by Einstein which is theory. So why gravity is a force that can extend unimaginable distances no one knows. What is the carrier for gravity no one has proven it. However it still remains as fact that gravity is an attractive force between matter. Its proven by simply dropping something from a height.
There is no point barking scientific models and protocols, when you dont understand your question or how valid are these models are to your study and field. Sometimes you can generate factual results without even using a control.
Gravity as a concept = fact
Description of gravity on earth = calculated mathematically
How gravity works = theory (can be further broken down into quantum and general mechanics)
you cant suddenly blend all of these aspects together of equal weight, each one is a different question and requires its OWN experimental setup, they can integrate with each yes but they are separate entities
so to my original example:
does drug A work = yes it shows superior effect over a placebo
how the drug works = unknown
but does that unknown factor change the fact that drug A works ? no it doesnt - the clinical trial has without a doubt proven that drug A works.
Antibiotic pyrazinamide will tell you in its package insert "its unknown" yet it kills bacteria in vivo and in vitro and is used to treat TB and is one of the main agents in first line treatment. The fact that its unknown on its MoA does not change the fact that it kills bacteria. No matter what you do mathematically, theoretically that antibiotic will always kill the bacteria that are susceptible to it. You can change its proposed mechanism a million times but that statement will never change and hence is fact.
EDIT:
however this again doesnt hold in biology, as I said earlier the scientific model is modified depending on the field its applied.
people often forget there are NO absolutes in science, that includes the method of science itself