- If you were a subject in an experiment, wouldn't you be curious about the experiment design and the hypothesis being tested?
- If you had a good guess as to the tested hypothesis, could that influence your behavior?
If the experiment was via college students, it is unlikely that anyone thought about the experiment design much, because students. This may be true of any adults in that time and area, maybe, as a (unnoted) selection bias. There was an implicit cultural deference to authority in the 70s that doesnt exist now (the thinking of the counter culture was also very different). Finally, there was a weak understanding of what terminology (like subject) implied or the inherent dangers, much less the ethical perils.