That seems so bizarre. All sorts of road debris should be getting stuck in that fashion but it never does. It’s all rather odd.
You're suggesting there's some inconsistency in the premise that incriminating debris from a singular incident would be stuck there for the long term even though mounds of debris related to every other use of the truck are not stuck there for the long term? Consider the immense amount of stuff that you drive over, including living and dead stuff, in all weather conditions. Yes, some stuff will get stuck and stay stuck, but 99.8%* of the stuff you roll over either gets stuck temporarily and later falls away or never gets stuck at all. What are the odds that a comparably tiny amount of incriminating debris from a notable singular incident would get filed under the "stays stuck" group?
*statistics
Methinks the only way this would be plausible is if the truck had a) not been purposely inspected & cleaned after the incident, and b) been used sparingly or not at all from that point forward. Doesn't a) seem very unlikely? I think b) is more likely than a). Although I suppose the same guilty conscience that blocks you from driving the truck again might also hinder a thorough inspection & cleaning. And I also suppose we can fall back on the "subconsciously he wanted to get caught" angle whenever things don't seem to add up.
...your speculation link does seem to require that one accept that the Saanich PD are complicit in railroading Mackay...
Here's the thing: I'm a straight-laced law-abiding individual and yet I have at least three personal experiences related to criminal investigations that reflect poorly on police and their investigative efforts (clueless incompetence in one case and deliberately fishy conduct in another case... in the third case I can make excuses for them because of the particulars, but even so they still didn't make a very good showing). When you get right down to it they're just fallible human beings working for other fallible human beings. How many times a day do police somewhere in the world deliberately do something they know isn't right or otherwise make a mistake? Thousands of times? If it happens there then it can also happen here.
But for the record, none of my personal experiences involved Saanich Police. If one department in the world can lay claim to being the cleanest and making the fewest mistakes then why can't it be Saanich PD?
Anyway, we're just having a Saturday afternoon yap over coffee.