Question:
I thought people were crazy for comparing these, but I layed the Green Valley on a bit heavy today, and kept catching whiffs of something distinctly familiar - and I think I only picked up on it because it's a nice sunny day and I have the windows open, so there's fresh air circulating in my apartment. It is something akin to Fahrenheit, buried beneath all that blackcurrant.
My updated opinion - yeah, there's a hint of something fahrenheit-like in there, but to overall say that these are similar fragrances doesn't really do either one of them justice.

Answer:
It might be one of the similar notes (violet perhaps in this case).

Check out this thread where a lot of comparisons between kiton, git, and kiton, fahrenheit were made:

/showt...ighlight=kiton