[felixchan]

Testing things is different than practicing things.

You cannot test many things. You also cannot prove many things. Look at nutrition. Determining the cause and effect of a substance on a human body is difficult.

Science is aimed at proving things. Sometimes, in life, that luxury is not available.

[Nextgrid]

You can't test/prove everything, however my understanding is that at least a large part of these quack treatments (if not all of them) have already been proven not being able to work (or being actively harmful) in existing medical literature.

[felixchan]

Perhaps you should rethink the concept of "proven not being able to work".