I know Luke and I saw him train in high school. His coach was Dan Quinn at Judge Memorial. What I know of Dan is that he is smart. Luke did not over train. What Luke did do very well was master high intensity workouts where he maximized opportunities to challenge anaerobic threshold. Luke definitely did not over train.
Luke was a phenomenal high school prodigy. I remember watching him run as a freshman in the mile. That year his teammate was Notre Dame standout Pat Smyth. Smyth was a 9 minute two miler, none of that phased Luke as he would just go all out from the gun. It seemed as if dying or failure was not an option. He started college on a high note as well.
So many factors can be causing this "stagnant" and often erratic running behavior. For one, he is young. Two, he is a student at one of the most pressure packed and academically challenging schools in the country. Oregon is a Tier 1 University.
Another option, perhaps the training he has been doing is not working. The proof is in the pudding. If you try something and do not like the result, tweak things, and try again.
I think Luke will ultimately end up at the 10k. I for one am a Luke Puskedra fan. I drove to Eugene to watch him try for the sub 8:40 attempt at the Prefontaine Classic. I also watched Alan Webb fall to pieces and Kenenisa Bekele run the 4th fastest 10K of all-time solo.
Two lessons, the first is that even record holders, champions, the best have off days, weeks, and years...welcome to the real world. The second lesson is that it's a 50/50 deal, at anytime you can come back, we all get in ruts.
My advice as a friend would be to run for the love of running and throw all the other crap out. Passion drives everything, find the passion, lace up your shoes and hit the trail. Go get'em Luke! We are all so proud of you here in Utah!