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There are not many sports that require heavy eccentric contractions more than skilled concentric contractions so excessive eccentric work would thus be contraindicated.

yeah...and they'd be better off just using depth jumps and depth drops

What do we really know about eccentric (lowering) work? The eccentric phase causes most muscular soreness. This causes much of the burn that bodybuilders talk about. The eccentric phase, when performed slowly, greatly contributes to muscle hypertrophy (growth). We also know that in an attempt to raise absolute strength, eccentric training alone fails miserably. In the late 1970s, Mike Bridges experimented with eccentric bench pressing. He told me that the only result he got from eccentrics was a pec injury. This is confirmed by research that shows that most injuries occur during the yielding, or eccentric, phase. Vince Anello also experimented with eccentric work, doing eccentric deadlifts with as much as 880. When he returned to conventional deadlifts, to his dismay his deadlift had decreased. Vince told me that anything will make your deadlift go up--except eccentrics. What does this mean? Are eccentrics a waste? Well, yes and no. Eccentric training alone is a waste. However, a strength-shortening cycle, eccentric training followed by a concentric phase, can be very beneficial when done correctly, i.e., with optimal speed.

My university's s@c department likes to use exercise selection and programming that I find questionable at best, they seem to like using the concurrent method with fullbody workouts and some "functional" training stuff. Anyway in one of the lower body strength days prescribed for the rugby team they had them doing heavy back squat negatives with 110% max for four reps, having two spotters assist the weight back up to the starting position.

My thoughts are that if you are weak enough to be able to recover from this sort of training you might as well stick to a simple linear progression and not worry about anything fancy. And if you are strong enough to benefit or need some kind of supramaximal training stimulus you would just burn yourself out and it would be incredibly dangerous to both you and the spotters. 

Is there any actual benefit from this type of training or have they gone full retard on this one? 

Sweet thanks for the info man, I completely forgot about weight releasers!

edit: it seems strange to me that an athlete would have minimal eccentric strength gains from concentric only training. If someone made giant gains in their deadlift say 400lbs, something way beyond the extra 30% strength of eccentric contraction and whatever minimal eccentric gains they get since they dropped the bar at the top on each rep.  Would it be possible that they couldn't at all lower their max deadlift?