Young is 27, how many more years does he need to "mature"?
You only need look at everyday life to answer that question.... Since when did someone being a certain age mean they are mature?
I think the fact that Fisher never accepted him has a lot to do with his actions... he admitted himself on occasions that he felt he was always one step be it injury or whatever from being yanked by Fisher. Don't know if that's true or not but could mean a lot if in fact it is true.
There are QB's that people gave up on in one place that shined in another... Steve Young was not considered a good QB until SF. Vinny Testeverde did a little something late in his career like Kurt Warner. I'm not saying Young is any of them but maybe he's a Bubby Brister or Chad Pennington a decent stop gap guy for a few yrs...