The most challenging work was the granite precision, and all of that was contained inside the pyramid for none to admire and be inspired by. But, if you were to presume they pursued precision in the chambers, as a way to honour the king, then that goal would direct them to do it in a softer stone like the limestone, which would give them the opportunity for the best precision, and choosing the granite instead, would have only created more opportunity to fail him in that regard.
"Hard work, for a good cause, under good conditions isn't suffering. "
If that were true, then if the goal was simply creating the pyramid as it is, they could have avoided all of the granite all together and saved themselves an enormous amount of difficulty and risk, but they didn't. They went with Granite, which significantly increased the challenge of execution without any real structural or even surface finish benefit to the accomplishment of the project. So this decision can only be attributed to your suggestion that some decisions may not have been necessarily 'practical' in terms of production efficiency.
But I suppose you can simply say, because they chose granite and successfully achieved perfection of precision regardless of that heavy disadvantage, then its existence could substantiate your presumption that they some how knew they could achieve it. But to me, that's what pushes your scenario into Occam's domain. And Ironically, this presumption of 'confidence' on their part is exactly what is behind my conclusion that they had a tech advantage, which is exactly why they had that confidence and freedom to make what appears to be nearly reckless production decisions.
Although, its a confusing point to argue because to me, I suspect based on the risks they took in the challenging material choices combined with that goal of extreme precision tolerances, that work wasn't actually as 'challenging' as one has to presume if there was no secret tech. And that point could be confusing, because by 'challenging', I'm not suggesting it was like balloon animals easy, but 'relative' to your traditional means of achieving those tight seams by chisel and hammer, it was easy in that comparative light. And I'll say again, that out of respect for Egyptology, I have to assume the existence of an unknown tech had to happen in non Dynastic times considering how complete the historical record is of that time.
It's why I wish more engineers wouldn't evaluate the relative 'welcome' of their opinions before they chose to jump into this ring. With the exception of the thoroughly ridiculed and exiled few like Chris Dunn, the rest share in common the relative palateability of their theories from the perspective of Egyptology. In my opinion, that's not a coincidence, and I'd also suggest its why those opinions are not a reflection of the majority of engineers, IMO, but we'll never know, because most of them wouldn't want to set foot anywhere near this convo, considering the reaction I see here usually.
The bottom line I think I can summarize is that we both have to invoke circumstances that are equally vulnerable to argument, but the tone many strike in this site regarding that comparison, seems to suggest that the comparison of that choice of invocations is nowhere near equally vulnerable.
This is where I struggle with these discussions. To me, the Ancient Advanced Civ edges out the alternative, which implies I afford that other view with the respect it deserves and its failing is only a marginal deficit. But when I'm put on the defensive, that doesn't come across very well.