Puzzle me this....
Unless you can positively confirm that the source of smoke or fire has been completely removed, a landing at the nearest suitable airport is required. That of course is the commanders call on the day (and what all the big bucks are for
). The remark in the QRH assumes that the recirc fan was the source (as it is a prime candidate). You are quite correct LEM, but on the day the flight crew will have to make the final decision on whether to divert or not.