I think it's far too late to add in realism.
Got to give them credit though, the world always knew that T-rex dragged it's tail on the ground until it was proven in the early 90's that T-rex didn't drag it's tail on the ground, just as the top minds are making this discovery the people doing Jurassic Park are picking up on this. Imagine if Speilberg just said, "Aw, f**k it, lets let T-rex drag his tail on the ground and stand up straight".
