I saw a special on a cable network about the possible american murders of Jack the Ripper a month or so ago that I found very interesting. Then I found this book and found it even more so.
Of course, like everything, it is all speculation but it does seem to have a lot of validity as a theory. Certainly the murder of Carrie Brown.
And of course the suspect, Klosowski was a favorite of Abberline among others. And the timing fits. The switch to poisoning is a major area for possible diagreements of course. WOULD a serial killer switch methodology that much? Lots of food for thought here if you enjoy Ripper theories though.