That's definetly an eye brow raiser, could be possible.

 

Let's just see what history has instored.

 

Fossils however need more correlation tho

Hmm...sounds very interesting, I will conduct further research on this.

 

I want to see if this adds up to their evolutionary branch. :)

Something interesting:

Abstract Megaraptorids are a group of predatory dinosaurs that inhabited Gondwana from Cenomanian to Santonian times (Late Cretaceous). Phylogenetic relationships of megaraptorids have been matter of recent debate, being alternatively interpreted as basal coelurosaurs, carcharodontosaurian allosauroids, megalosauroids, and basal tyrannosauroids. One of the main reasons for such different interpretations is the incomplete nature of most available megaraptorid skeletons and, in particular, the scarce information about their cranial anatomy. Here we describe a partially preserved skeleton of a juvenile specimen of Megaraptor namunhuaiquii that provides substantial new information about the cranial morphology of this Patagonian taxon. The specimen comes from the Upper Cretaceous (Turonian–Coniacian) of the Portezuelo Formation, northwestern Patagonia, Argentina. The anatomy of the new specimen bolsters the recently proposed hypothesis that megaraptorids are nested within
Coelurosauria, and possibly within Tyrannosauroidea. The most relevant features that megaraptorans share with tyrannosauroids include several foramina on the premaxillary body, extremely long and straight prenarial process of the premaxilla, incisiviform premaxillary teeth with a D-shaped cross-section, and cranially expanded supratemporal fossae separated from each other by a sharp sagittal median crest on frontals, which was presumably extended caudally above the parietals (not preserved). Information gathered from the present specimen allows to make for the first time a reconstruction of the skull of Megaraptor and hypothesize about evolutionary trends within Tyrannosauroidea.

Damn paper's paywalled, but if anyone thinks they can find it, here's the citation Juan D. Porfiri, Fernando E. Novas, Jorge O. Calvo, Federico L. Agnolín, Martín D. Ezcurra & Ignacio A. Cerda (2014) Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation.

Anyway, i guess this shook things up quite a bit. Here's what the
megaraptora family tree looks like nowadays
Megaraptora  

Siats

  unnamed  

Fukuiraptor

  Megaraptoridae  

Eotyrannus

     

Australovenator

   

Rapator

    unnamed  

Orkoraptor

     

Aerosteon

   

Megaraptor

           

 

However, we must keep in mind the fact that Tyrannosauroids
aren't Tyrannosaurids.
For example:
Tyrannosauroidea Proceratosauridae    

Proceratosaurus bradleyi

   

Kileskus aristotocus

   

Guanlong wucaii

       

Sinotyrannus kazuoensis

     

Juratyrant langhami

   

Stokesosaurus clevelandi

           

Dilong paradoxus

     

Eotyrannus lengi

     

Bagaraatan ostromi

     

Raptorex kriegsteini

     

Dryptosaurus aquilunguis

       

Alectrosaurus olseni

   

Xiongguanlong baimoensis

       

Appalachiosaurus montgomeriensis

       

Alioramus altai

   

Alioramus remotus

    Tyrannosauridae    

Gorgosaurus libratus

   

Albertosaurus sarcophagus

    Tyrannosaurinae  

Dinosaur Park tyrannosaurid

     

Daspletosaurus torosus

     

Two Medicine tyrannosaurid

     

Teratophoneus curriei

     

Bistahieversor sealeyi

     

Lythronax argestes

     

Tyrannosaurus rex

     

Tarbosaurus bataar

   

Zhuchengtyrannus magnus

                                      Went off-page there; here's the link:
http://en.wikipedia.org/wiki/Tyrannosauroidea

Siats would, theoretically, be the largest basal
Tyrannosauroid based on these cladograms, if they're proven to be correct.
Interesting stuff considering the time frame it occupied..  

Weren't Siats smaller than T.Rex?

Well, technically, that size comparison is of the "juvenile" Siats specimen, so it is accurate as far as length goes. The holotype is 9 meters, but the adult size is probably around 11-12 meters.

 

Glad you like the post :)