Thanks for sharing John's post and hist excellent blog. I think the best way to avoid memorizing is to have a deep understanding of the subject. If you are giving a 7 minute speech, you should research and collect enough material to be able to speak for at least 30 minutes.
Thank you for the list. I attend a toastmasaters club and started a blog site to help the club members with communication articles. I will try to popularise my site with your suggestions.