What's she got to lose? Do you know for a fact that her saddle is in the correct position as is? I'd say that if it fixes her CTS problem it's worth a shot. If her knees get sore then, sure, it did not work. But, who's to say that it will cause a knee problem? There's probably just as good a chance that it won't cause a problem. If you have a threadless headset there is not a whole lot you can do with a bike to make the body position more upright - short of replacing the fork or stem - other than moving the saddle closer. It's a trial and error process. Anyone that gets an absolute perfect fitting right off the bat is pretty damn lucky, but, that being said, a competent fitting is very important to get a good starting point. So, short of getting a fitting and a new bike, you work with what you can.