I was watching an interview the other day with Kurt Warner. He said he likes all the tools that Trubs brings to the table, but he was concerned about Trubs ability to "handle an NFL huddle". Those were his words and he probably knows a little about playing QB.
For him to say that, as well as others, there must be something about him that makes people, if nothing else, wonder about his leadership skills. None of this keeps Trubs from being a good QB, but it could be the difference with him being a great QB. NONE of anyone here knows for sure at this point.
The OP brings up one of the more legit concerns about Trubs compared to a bunch of other crap being said. However, I believe it was his OC who said he's the most accurate QB he's seen in 30 years, so good play fixes most everything.