Mr. Locklin--
First, time and again I have seen that only the most sophmoric discount another's view of training because, intuitively, you "know" that the person is "slow."
You have adopted the fundamentally unsound strategy, when your argument fails, of attacking the runner who you do not know, lamenting his "slow" times. Someday you might just encounter a sub-4:00 miler, and where will you be then?
As for the study, that is a commonly bandied about piece of training "wisdom."
Few will argue that there can be benefits to plyometric training, but as the 5,000 meters is a LONG DISTANCE running event determined by AEROBIC energy sources predominantly, training like a sprinter for an inordinate amount of time will do precisely nothing for you come race time.
Further, that study, as I remember it, seemed to use MEDIOCRE athlete times by your own apparent standards (there was one that had a number of 20 minute 5K runners) and therefore the result is a study that applies to NON-ELITE athletes.
I would not put so much stock into studies of that nature (or similar studies where a scientist puts a RAT on a plyometric program, sees its 5K time improve, and Owen Anderson proclaims that doing any running slower than speeds that elicit 90% of VO2 max is a "waste").