Why are they not all agreeing even though they are equally experts? Because they dont have enough data to back their claims 100% up, and this is exactly what is happening. [...]
Fact is, the arms of the Spinosaurus Aegyptiacus CLEARLY arent legs and never was meant to be walking on.
It's just a possibility. As far as I'm aware, the authors don't claim that this is the only conceivable way how Spinosaurus would have walked. What they claim are the proportions of the skeleton, which make the traditional reconstruction unfeasible.
What you are doing is, you're dismissing their results a priori because of their methods. They are professional learned paleontologists, so I suppose they know what they're doing. If they combined different specimens for their reconstruction, I assume that they made sure that the specimens are comparable. And that's what I gather from Ibrahim's response to Hartman.
Unless someone can prove that their methods are wrong (by coming up with different results by working with the original material), the results stand as our best and most up-to-date picture of Spinosaurus.
You say that "lots" of other experts question Ibrahim et al.'s results. Can you link me to some of those? All I know of is Scott Hartman's initial reaction and others jumping on that wagon. But Hartman never doubted Ibrahim's findings that Spinosaurus was semi-aquatic and had unusually small hindlimbs, just that they were as small as shown in the reconstruction. Mark Witton got similar results to Hartman, but after getting more precise data from one of the paper's authors, he got results that matched their own and took his criticism back.
How Spinosaurus moved on land is a puzzling question, but without further work on the subject there is no reason to refute the new findings (especially not because "it looks strange").
Also, all the other Spinosauroids from the era was walking on 2 legs, not all 4, why would the Aegyptiacus suddenly be doing that, especially with arms that was not designed to do it?
Evolution. Adaptation to a lifestyle. If I'm not mistaken, Spinosaurus is the most derived member of Spinosauridae. There can be considerable morphological variety within one family of animals. The familky Scincidae includes species with and without legs.
It was already evolved million of years before from walking on 4 to 2, why the hell would it evolve backwards when its cousins didnt?
Why the hell would whales evolve flippers from legs when their ancestors evolved legs from fins? Stupid whales.
Im an engineer, I know very well what I am talking about. A hypothesis which cant be proven is utterly worthless. Else, lets then talk about how unicorns exists, even though there hasnt been a single sight of them ever. Or are you sure we dont need any proofs before saying they do exist? ;)
Sry, I'm not so sure you do... A hypothesis that can't be disproven (i.e. not falsifiable) is worthless because there is no way of knowing whether it's correct or not - you can't prove that unicorns don't exist, so a hypothesis that postulates the existence of unicorns is not scientific. But until a falsifiable hypothesis is disproven, it is assumed to be correct. There are lots of things that can't ever be proven 100%, simply because we lack the means to do so.
Oh, and several people in this thread has already talked about what OP linked too clearly was wrong, and that the rearlegs indeed was bigger, so my initial statement are therefore correct still.
Well, just read the posts I linked above.