Comey is not continuing an investigation. He is trying to figure out how to word his announcement “clearing” her. But it won’t make any difference because Trump will indict her and convict her in the court of public opinion.
I choose not to believe that. I’ve known Jim Comey since he was the US Attorney for the Southern District of NY and the Deputy Attorney General (the latter under a miserable and inept Attorney General, John Ashcroft). He has always been a very honest and principled man and, while I wouldn’t expect him to publicly fall on his sword, in the event of a whitewash, he’ll make his opinion clearly known in a very public way.