Double blinding is not a means of making an experiment scientific. The only condition that makes an experiment scientific is a control experiment, in which we remove the test conditions in order to make sure that our results are not due to something other than our test conditions.
That is exactly what a double blind study does. The subjects are treated exactly the same. The only difference is that one group is given a placebo (or standard of care) while the other group is given the experimental drug. The people collecting the data do not know which group each subject is in so the results are not biased by the data collection process.
It is fine in the control only. In drug trials the doctors are relationally distanced from the patients or in other words the experiments are double blinded because they were trying to get rid of the problem of placebo in the group getting the drug because through ESP, which is at a premium in relationship, the patients knew that they were given a drug.
In the case of a double blind study, the doctor doesn't even know if the patient was given the experimental drug. The experimental drug and placebo look identical, and they are administered in the exact same way. The labels on the packages do not say if they are placebo or drug.
It is also worth noting that double blinding doesn't always help solve problems. So for instance in drug trials double blinding hasn't solved their problem to better determine the efficacy of a drug because all patients being blinded (ie loss of insight) means that there is a placebo effect now right across the board, in both groups those getting the drug and those getting the blank. Patients reason that they have a 50-50 chance of getting a drug so why not just believe they have been given a drug.
That is the entire point of a double blind study, to determine if the drug does better than the psychosomatic reaction. If the drug group data is equivalent to the placebo group then the conclusion is that the drug is not effective.
Remember patients in drug trials have a desperate need to get well and this is a strong motivating force to make such a choice.
In these types of studies the experimental drug is compared to the standard of care. For example, a new cancer drug will be compared to an already approved and common treatment. It is against the law, and ethics in general, to give a placebo to a patient with a serious disease. However, the doctor does not know which treatment is being administered, and neither does the patient.