I didn't find this article useful at all. The interview should speak for itself. If I am good, I need not write such follow-up mails. Also, if I show too much of a keenness, it is likely that my salary / benefits will be compromised. Again, decisions whether to send the candidate to the next round are taken right then, sometimes before the interview ends. One doesn't wait for 24 hours to take a decision, expecting a follow-up mail. Somehow, I don't find this situation realistic. . More importantly, I also take interviews and we are not encouraged to share personal information with candidates.