Here's the YouTube video. I don't think it'll go viral but hopefully you'll see that I kept good form. Danielson's 5 min plank: http://youtu.be/nlpG0xfQits
Personally I don't think there's much to gain from going over 5 mins that you couldn'tgain from spending the time doing ssomething else. I feel like I gained more for a running benefit mentally rather than physically because it's taught me how to deal with pain a bit better.