Don't disagree with anything you say here, but I don't believe that any of those factors justify the drop in utilization that we witnessed from 2010 to 2011. Hammerschmidt only had 13 receptions last season. Throw Branderhorst in there, and they had 23 total between the two of them. Compare that to Franklin's 54 receptions in 2010.
Clearly, some of that is due to talent differential from year-to-year, both at the TE and WR positions. But I have a hard time believing it wasn't also due to choice- perhaps a progression/evolution of Herman's system. Hell, Hammerschmidt only had 8 more receptions in 2011, without Franklin in front of him, than he had in 2010.
I could be all wet, but I think we have some untapped TE production to take advantage of.