My final contribution to this discussion is this. The OP advocated self assessment, at the same time he decided that people that were round shaped should not be diving. Period. Interjecting your personal bias and prejudices into a conversation about self assessment is the oxymoron here. I'm done with this.
p.s. - I don't think that, if they are in bad physical shape, any of the Hebes, Pollacks, WOPs, Limey's, Colored's, Mackerel Snappers, Micks, Chinks, Coon Asses, Krauts, Gimps, Beaners, Scrobs, Crotes, Peckerwoods, Crackers, Hags, or Mo's should be diving any more than the fatso's, doughboy's or whelephants. Did I miss anyone?