So Storker. How do you (general you) decide. What weight is the cut off? Do we use BMI? What age? Given the trend on the A&I forum prehaps just stop any male over 50 from diving. Exercise stress test? Not all that acurate in predicting an MI, especially in women. Who decides? General PCP? Should we all be required to see a dive specialist? That just transfers liability from the diver to the medical professional.
The answer to over litigation is not restriction of personal choice.
Nobody really can draw a line in the sand that is a working weight. The only working solution is changing the attitude of scuba diving being a 'fat man's sport' as I've heard it called for the last 20 years. The attitude in the industry has to start changing from the active participants. Typically the fatest bastard in the world can scuba dive on a good day and never have a problem, this unfortunately by many becomes the answer to the general question instead of being recognized for what it is. The old "I'm 300 lbs over weight and have dived for 20 years...." you fill in the details to that general statement : Dives 4 dives every 2 years in 20 years, all dives have been in warm caribbean water under ideal conditions.... It's when the good day turns difficult that the problems start surfacing. You add 6 foot swells to the equation... or you add their first dives without a dive master in the water with them... or you add a new piece of unfamiliar gear to their equation... any number of things regarded as insignificant can take that person to zero margin of safety and error quickly.