The problem with asking the experts about something genuinely new is, according to Heinz von Foerster, that they will only explain to you why it can't work or why it is a bad idea. We had no shortage of such experts in the past years :) However, common objections like
"e-mail is too slow", "secure e-mail is not possible", "you can not do a Whatsapp-style interface on top of e-mail" are having an increasingly hard time to be upheld because of the reality of Delta Chat apps working :)
aral