Hi Geoff, 
You said:
 
> So, you mean  Stefansson was only checked(re 
> urine/analysis/ketones)  to see if he'd eaten any carbs, not 
> for vitamin or mineral-deficiencies etc.? 

No, that isn't what I meant. I simply meant that a very steady, high level
of ketones, established during their hospital stay, and maintained
throughout the year, is sufficient evidence to accept that they ate no
carbs. 

> Mind you, liver 
> contains some carbs(one reason why zero-carbers often 
> recommend against it), and that was part of his diet, from 
> what Stefansson himself stated.

Based on that argument, muscle meat would also have to be eliminated because
muscle cells also make glycogen and store it. As long as liver was eaten at
the hospital, ketone levels would have been established. By maintaining
those same levels we may reasonably infer that the test subjects were
clearly not eating carbs. 

Best Wishes, 
Ron