Ok I understand the argument about being taller and running taller makes you an easier target. I get that. I also get the fact that there are not and have not been very many 6-4 running backs in college or NFL.
Here is one thought on why that is. Starting early in a football players career, if that player is playing tailback but is built more like a receiver or tight end, coaches might switch them to a position that more fits their body type. Does that make sense? I's that logical to you guys? Seems legit to me.
Now there are guys that came up having more of a reciever body type that insisted on playing tailback for one, either somebody told him would not excel at that position or two he wouldn't play football period at any other position. Mr Hurd was told that he wouldn't make it as a tailback but guess what. Look who's an SEC tailback. And so far a fairly successful one. Do you all think that he did not know the punishment he was going to receive being a taller back? Sure he did. Didn't matter to him. Will he make it to the NFL? I think he will and given his other skill sets I think he will be successful there also.
No, there haven't been a bunch of tall backs make it in the pros. BUT, you gotta admit, the ones that did were pretty good backs.