In these discussions, I'm not sure if Prof Edwards is aware of Snells research into the post exertional malaise and his test - retest protocols . Snell was trying to get a handle on metabolic data that shows, and it does show, that activity does exacerbate symptoms. Would these tests be useful in selecting patients for the trial? I know it seems like punishment, but then atleast you would have a set of patients who all had (hopefully) the same metabolic defect. Please watch this, if you are not familiar with the work of Snell et al. Incidently , it looks like none of us would qualify for a heart transplant as results show we are sicker than patients that meet entry requirements for heart transplant.