Tyrannosaurus vs Spinosaurus

Kangaroos are inclined to disagree with your idea that the tail hinders its agility.

And 8.4 tons comes from Hartman (2013) and the estimate for FMNH PR 2081, and even then, Hartman used a high density, taking that into account FMNH PR 2081 would be ~7 tons. Even then, that's our largest specimen, and I don't see why we would give it such an advantage.

You didn't get the point...

The tail does not hinder its agility considerably, it's just being dragged around, nothing more. It hinders its speed, not its agility. A kangaroo ain't unagile when it's not hopping. And my argument doesn't have to do with it being restricted in movement...

Komodo dragons, crocodiles, and many other lizards all disagree with that as well.

apparently you forgotten the citation mecha posted earlier that shows that those short little legs can support all it's own body weight and even offorst a mechanical advantage for locomotion on 2 legs. spinosaurus legs are just as thick and muscularly built and actually fencer then any other theropod, just shorter in stature. that being said, i doubt spinosaurus was particularly agile. matter of fact, i doubt any large theropods were relatively quick turners, and tyrannosaurus was no exception. in large theropods, the bio mechanics of the cuadofemoralis anchoring to the tail and thighs, rendering the tails very rigid and decrease the possibility of quick, pivoting turns. although i imagine it to be a little slower, i believe spinosaurus can effectively keep tyrannosaurus in front of it at all times.

this is a missmatch in favor of spinosaurus. spinosaurus has once again went through a new reconstruction. the isotope ratio in the bones have readings of radiation in it, the same type of atomic components of nuclear warheads. what is strange is that it seems to been able to channel the radiation without the occurrence of death. it is believed it could of been a defensive mechanic, causing instant death to anything it views as a threat. this is the new, and most accurate reconstruction.

A new study suggests that Tyrannosaurus Rex had an organ in its throat that acted like an enhanced flamethrower. It is believed that T.Rex itself was completely immune to the high temperatures of it's fire and was therefore able to surround itself in an inferno as a defense. The new Tyrannosaurus Rex reconstruction looks like this.