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Old 12-17-2016, 07:22 PM
kjab3112 kjab3112 is offline
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[quote=Pierre;403493]
Quote:
Originally Posted by kjab3112 View Post



Hi,

I am very interested in what you are writing here and will comment on it in all itīs parts. "Natural drift of a straight line" - I have never heard of the concept. Is there any research for it?



And "better" is an ordinal variable so there is a possibility of different values. Therefore, how can we say that this variable is important in the case of handedness and in what way?

Also, if you convert the variable you get the variable worse. In what ways would such a variable change the idea of the killer trying to obtain a "better" position?



And when you say "pure" opinions, what is that "purity"?

And the opinions, why do they differ?



The "if" is a problem and the "a right handed...would be more likely" is a problem already, which started a long time ago, and I would like to avoid that problem here right now. So not trying to determine the handedness - but trying to determine why the discourse is as it is.

So, what do you think about all this?

Regards, Pierre
Hi Pierre

Regards drift: the hand position is determined by the relative pronator and supinator muscles of the forearm. As the elbow is flexed and extended that alters the wrist position. If one draws a straight line there will be drift and lift off due to this change in wrist position. Surgical training is about avoiding this biomechanical reality.

When I refer to better I am considering the most natural position. As a thought experiment switch your knife to the opposite hand, you will find the plate has to be turned. The same for the murderer, because of the walls etc the cuts were much easier on one side and in fact would not have been even possible in most cases from the opposite.

Pure is a descriptive adjective of the opinion expressed at the time by the witness. There is no evidential backing except for personal experience. I.e. Pure opinion

For most likely position and hand look at my first reply. My personal opinion is that we don't know who killed the canonical five, but looking at the surviving autopsy evidence they were likely killed by the same hand with MJK more similar to Annie and Polly than the double event but with sufficient similarities to be at reasonable doubt level.

Best wishes

Paul
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