The coach hasn't gone out of his way to endorse Hill as next years starting quarterback. IMHO I think he is looking to upgrade the QB position for next season.Why spend the money on Cassel? You have as good if not better QB in Shaun Hill. You need a 3rd QB, but it's not a big issue if Alex Smith is ready to go next season. If not, then obviously you need 2 QBs, but I'm certain Hill can do the job.
If the 49ers are going to bring another quarterback, then I would rather have Stafford than Cassel.