Thanks for the example of the BTK killings, well said. One of the reasons PGP insist that Kercher had to have been murdered by multiple assailants is that this somehow, in their twisted minds, raises her heroic status. Witness them always bringing up her very elementary skills in martial arts as if this somehow "proves" that more than 1 person "had" to have been involved. One wonders why they never seemed to apply this "reasoning" to Jody Arias having managed by HERself to stab her ex(?) BOYfriend to death.
Ah but the Arias case is a bad comparator, because (IIRC, as the evidence shows), she set about her bf in a rage. And indeed (again IIRC) he did have defensive wounds to his hands and arms.
And that's the cornerstone of Vixen's ignorant belief in respect of the Kercher murder: if Guede alone was the perpetrator, one would expect Kercher to have sustained signs of defensive injuries - whether in the form of knife wounds to her hands/arms or punching/throttling injuries etc. Vixen ignorantly goes on to claim that the absence of any such defensive injuries on Kercher's body necessarily proves that there must have been multiple attackers (one or more of whom held Kercher down while one or more others assaulted and stabbed her).
But that's precisely why an example like the BTK case is extremely relevant to any examination of the Kercher murder (and why something like the Arias case is actually much less relevant). If there is a sole perpetrator, and one or more people end up murdered, then typically there are two main ways in which the situation evolves:
The first (e.g. Arias case) is where the perpetrator clearly sets out from the beginning of any physical confrontation to harm the victim(s). For example (again probably e.g. Arias) the perpetrator comes at the victim(s) with a knife and/or gun. In this scenario, the victim clearly knows, right at the start of any physical contact (in fact, often before any physical contact) that the perpetrator intends to harm them severerly. And that's exactly why, in this scenario, one would usually expect to see some level of defensive injuries to the victim - e.g. knife wounds to the hands and/or arms where the victim has tried to prevent or deflect knife strikes.
But the second (e.g. Guede/Kercher case or BTK case) is where the perpetrator initially demonstrates that he has the means to inflict grave harm to the victim(s) - whether by brandishing a large knife, or revealing a gun, or even occasionally by being so physically superior the the victim(s) that it would be obvious to the victim(s) that they could be easily overcome and badly harmed. That's an important first step.
And then the second step is that the perpetrator goes on to verbally (and/or using gesticulations) deceive and control the victim prior to any physical confrontation. Typically, this takes the form of some variant of "carrot and stick" approach - e.g.
"Get on your knees and put your hands behind your back: do what I tell you and I promise I won't harm you; but try to resist, run away, or call out, and I'll badly harm (or kill) you"*. In this scenario, it's very unlikely that the victims(s) would believe (or even risk believing) that the perpetrator's ultimate true intention is to kill them; and that being the case, the victim(s)' logically-optimum choice is to comply with the perpetrator's instructions.
So now we have a situation where the victim(s) has/have chosen to comply - but by doing so, have placed themselves in a much more physically vulnerable situation (for example, the BTK killer persuaded his victims to let him tie them up (or in some instances, tie each other up....), and it's probable that Guede persuaded Knox to get on her hands and knees and allow him to hold her from behind with his knife at her throat). In turn, this means that the victim(s) is/are almost incapable of defending themselves if the perpetrator does decide to inflict serious injuries.
And this, in a nutshell, is almost certainly the reason why Kercher did not exhibit any defensive injuries: Guede had already forced her into compliance (by using some form of the psychological trick outlined above), and by allowing herself to get into a situation where any further form of defence was near-impossible (since she reasoned it was better to do what Guede said than have him rush her with his large knife....) she was effectively unable to defend herself against the ultimate fatal knife attack: Guede's knife would already have been at her throat, and there would have been no way Kercher could do anything about him going on to stab her in the throat. And thus no defensive injuries.
* Often it won't even be necessary for the perpetrator to spell things out in this level of detail - exactly the same implication can often be accomplished in very few words and/or gestures (remembering, of course, that the perpetrator has already shown the victim(s) that he has the means to inflict great harm or death upon them if he so chooses....)
