I spot a pattern in some Ripper non-fiction: First the author throws lots of information on the Ripper-murders and some of the circumstances at the reader, then he/she infodumps on their choosen suspect and hope that nobody notices that there is barely any connection between those two. It's the same with this book. All Wilding has is that Mary Kelly was often in London's West End and MJ Druitt had his solicitor-office in the West End. From this he concludes that after Mary Kelly got pregnant by the Prince of Wales (yeah) she went to him to ask for advise. He went on to tell this to J.K. Stephen who panicked because had a massive crush on the Prince and worried that if it ever got out that he'd impregnated a Catholic whore the monarchy would crumble so he went out to kill her (but kept on killing the wrong person...well twice and then it gets even more obscurer and involves Queen Victoria...please don't ask).
Then there's a lot of stuff about anagrams in various messages from Jack (Stephen wrote those because...reasons). Also the last third of the book contains more subjunctives than I ever saw in one place.
Even if you ignore the fact that the theory is completely insane the writing itself is also...lacking. In the first chapters on the victims he uses variations of the sentence 'She didn't yet know that this would be her last night on this earth'. I already find those incredibly annoying in fiction. In non-fictions they're just out of place. Besides the way he wrote about the victims just made me feel...strange and slightly uncomfortable. He kept pointing out how poor and unlucky they all were over and over again, as if it wasn't enough describing the circumstances of how they all ended up on the streets, no apparently the reader is so brain-dead that he had to be told that this meant they were very unfortunate.