Did the murderer have anatomical knowledge beyond that of say a butcher?

[Trevor Marriott]

No.

I read an interesting article a few weeks ago by a veterinarian.

He wrote that the murderer did not make incisions according to the prescribed surgical method.

His only doubt was that he did not know for a fact that the same method was used in 1888 as is in use today, and it would be interesting to hear from someone who knows (assuming he is living in the right century).

He explained in detail that the incisions - I remember he paid particular attention to the initial incision - made by the murderer were not in accord with surgical practice.

That`s correct Eddowes was initally stabbed several times through her outer clothing both in a downwards and across motions. The decscription of the cuts to her clothing confirm this

“Chintz Skirt” – three flounces, brown button on waistband, jagged cut six inches long from waistband, left side of front, edges slightly bloodstained, also blood on bottom, front and back of skirt.
“Brown Lindsey Dress Bodice – black velvet collar, brown metal buttons down front, blood inside and outside of back of neck of shoulders, clean cut bottom of left side, five inches long from right to left.
“Grey Stuff Petticoat – white waistband cut one and a half inches long, thereon in front edges blood stained, blood stains at front and bottom of petticoat.
“Very Old Green Alpaca Skirt – jagged cut ten and a half inches long, through waistband downwards, blood stained inside front undercut.
“Very Old Ragged Blue Skirt – red flounce, light twill lining, jagged cut ten and a half inches long, through waistband downwards, blood stained inside, outside back and front.

www.trevormarriott.co.uk

[PRIVATE INVESTIGATOR 1]

The blood around the victims did not show any spray, which indicates the victims were already dead (strangled) when the throats were cut.

I think JTR learned from the early cases where women were attacked with knives and managed to escape… His MO then changed to strangle the victims first, prior to mutilation

Which early cases do you have in mind?