As advised, this has been debated with mich gnashing of teeth by confirmed Reacher fans, of whom I am fevetly one.
For me, it is not just the height issue with tiddly Tom, although that is obviously an issue - it is simply his utter lack of prescence that will make him wrong for the part.
I have never understood why TC is revered as an actor, to me he is wooden, samey, utterly without conviction, and lacking any basic ability to inhabit and project a character on screen.
For these reasons, he will be almentable as JR - and I am amazed at Lee Childs sanctioning such a move.
Given that the picture of the man on the hardback jackets is actually the author himself, maybe they should have cast him the role!!!