Pretty interesting. Before jumping to conclusions let me ask how many variables (time of day, wording of subject, frequency of sent emails, history of relations

Pretty interesting. Before jumping to conclusions let me ask how many variables (time of day, wording of subject, frequency of sent emails, history of relationship with the recipient etc.) can you claim to "have under control"? Did you start CCing Alex for all 70 recpients? I'm asking coz there might be several explanations for the effect (assuming it's statistically significant and methodologically acceptable)