Dan Pfaff and Boo could speak more to this but Posture control is important. Most of the work core, strength, fitness, or what you would like to define it is important for all athletes but even more so for distance runners as some short events people can get away with poor posture and “muscle” through. Obviously, once a 1 rep MAX has been established those types of loads of 40-50% might only be used in certain times for restoration or other types of training modalities. However, I think it would be very difficult to establish what someones max would be on a single leg clean and step up. Many of these lifts were multi-movement in nature.
I will never train my distance runners as power lifters. Considering the top kids I coached in the last couple of years were nationally ranked in high school and still nationally ranked in college I feel very comfortable with what phases we do and the gains our kids get out of this training. Everett at Columbia, Robison at Arkansas, and Sisson at Providence if you would like to see what these kids are doing now. Do we max lift with our distance kids? Yes. Do we try and do some heavy lifting for long periods of time? Yes. Do my distance kids Olympic lift? Yes.
But, that doesn’t mean what Galen is doing in the video has no value. In addition who is to say this is all Galen does in a session I would imagine he has many different phases that have been set up with a periodization scheme. Galen might not even be all that strong to begin with and could still be climbing up in the load category as he learns these lifts.
I’m not saying this type of work has no value. I’m saying its not strength training as most athletes define the word ‘strength’. Neither Boo nor Dan would refer to this as strength training, IMHO. Posture training, stability training, whatever. But I think Mike’s suggestion in the OP is that true strength training could be beneficial to endurance runners. I don’t know that answer, but I think it is important to keep the terminology straight. If its training to improve stability, call it stability training. If its training to improve posture, call it posture training, if its core work, call it core work. If its work designed to improve power output, call it power training or explosive strength training. But I think it is wise to associate the term ‘strength training’ with training designed to improve max force output, since that is how we define strength.