That tweet was sent out around and the time the project website was edited to immediately indicate the end of the study (instead of continuing it to the spring), and adding a FAQ that tries to dispel concerns about IRB approval and email address harvesting.
That makes it seem unlikely he was unaware of the negative responses to his study.
That is true, although I think it would still be a poor choice of words to say "overwhelmingly" without tempering that with a note about assuaging the fears of some few that misunderstood the nature of the communication. Assuming he was aware that some were stressed and involving legal council.
The "secret shopper" justification for not informing participants ahead of time about the study can only take him so far, and I don't think it was necessary here to begin with. His research is to determine the policies in place at target recipients' organizations, and that doesn't require secrecy. In fact that justification undermines the exemption status of the study: he expected that people may react differently if they thought it was a user vs. a research study.
