I don't think the results in the link I posted are complete - you would have to read the thread from the beginning and try find the full text of the study they are referring to - I'll try to do this myself when I get time.
BF by skin calipers and also some fancy machine that sends electrical signals through multiple points on the body - not just the legs like some I have seen before. Both give more or less the same reading, the machine slightly higher.
She isn't entirely new to training - but shes been more consistent and trained harder and more frequently as of late (few months), instead of casual, with some encouraging results.
I can appreciate that the best thing to do is try for one or the other, so you don't make a rod for your own back, but 'impossible' just seems so absolute. 'Highly improbable and not advised' might be a better way to put it.
You got your bases covered then as well