I completely agree that game experience helps. The question is, what constitutes a wasted season of eligibility?
To me, if Dungey gets enough snaps to tally 50 pass attempts, he probably has played enough to make a difference for how ready he may be to take they keys in 2016. I'm using passing attempts as a proxy for a lot of things - those 50 pass attempts probably happen over some 100+ plays, when how he performed actually mattered in determining the final outcome, and that's also enough passing attempts where he's likely thrown a TD or two and knows what it feels like to make a play that gets his team on the board.
If Dungey plays at all and has less than 50 pass attempts, I don't think it's done that much for him being better in 2016 than he would have gotten without that PT. Now we've lost the potential for a 5th year senior season. To me that's a waste, and exactly the kind of thing that really damages our football program.