If this was MY study, participants would eat the exact same gummies, same strain, same strength, with a measurable dosage.

That's the purpose of well designed studies, to determine what, exactly, is the controlling factor. If you have too many variables, coming to any sort of coherent conclusion isn't really going to happen. Control the number (& intensity?) of variables & we might get something useful from a study.

I don't know, is there a difference in results by source/strength of alcohol? In other words is drinking sherry comparable to drinking moonshine, & then driving?