Yes, they were purposefully silly, to point out how "silly" the entire debate is.
The injury obviously played a part, and that is a reason, as opposed to an excuse. Why bother arguing with irrationality?
That still has nothing to do with what Herbert was able to accomplish.
His season was an anomaly for a rook, and I seriously doubt a completely healthy Tua would have put up numbers like that, for a couple of reasons.
Flo is not a sling it around type coach, as long as the score is close, and the D is playing well.
Tua doesn't have the arm to force balls like Herbert to begin with. Don't get all defensive, his arm is plenty good enough. Tua's strengths lie in processing, touch and accuracy, and that is much more difficult to showcase as a rookie.
My point is, bringing Herbert into the discussion at all is apples to oranges, without even getting into the injury. I would also say that any outside, non biased observer would say Herbert looks like the better pick at this point ("at this point" is key). That doesn't mean that their career trajectories are written in stone.