> [...]
> This presentation would have been accepted if we had seen speaker talked at local meetup groups, had a recorded presentation we could view, or maintained a blog so that we could foresee of how he would present his ideas and build an argument.
Perhaps we were outliers, but @buu700 and I were accepted to BlackHat and DEF CON with no prior speaking experience outside from a dry run of the talk to a single meet-up.
One delivery -- and the talk as delivered in both conferences ended up being far different from that specific instance. Now if the article suggests that just doing it once is fine, cool, but if it's suggesting a track record of past smaller conferences, I'm inclined to disagree, as are the reviewers for the largest conferences.
It helps, but being bereft of it certainly doesn't disqualify you.