One of the hallmarks of RCT in medicine is that each participant is informed of the risks and benefits, and then freely gives informed consent to participate, knowing the risks. Do RCT's at the village level include informed consent, and if so, how is it obtained? Is everyone in the village capable of understanding and agreeing to undertake the risks and benefits?
Research on humans (and other biological subjects) is difficult and messy. Pure randomization is not possible in the way that a chemist can achieve. Conditional randomization seems the best way to go, but interpretation of the results is more complicated.