I've been coaching our boy's squad heavily based on Tinman principles for the last 2 years.
For the juniors and seniors on varsity, 60min/day is pretty close to what we do, including workout days. The top runners (just three of them at the moment) go up to 90min for their long run, but the majority of the team won't go higher than 10 throughout the season, so anywhere from 68-85min for the majority of the team. Previously I was using Daniels as it worked for me in hs, but I found many of the workouts to be too difficult for even the top runners. I also found my athletes who weren't ranked in the top 5 spots to actually complete a run when told to do it in minutes versus miles. Also creates a pretty consistent finishing time for all of the athletes.
We had a standout freshman this year (16:23) who I told from week one I would be limiting his mileage and workouts and to trust me that it was for his long-term development. We had two stars (a pair of twin brothers who both ran 14:59 this season) who are pretty accustomed to doing 3 mile warm ups and cooldowns after workouts. I would have the freshman do 2 up and 1 down, and usually 2 less reps than the seniors.
Another thing I found to be successful was to create a "team long run" culture. I used Twitter to advertise a weekly Sunday long run on dirt roads close to many major schools. We had team members from 5 different schools including our own show up and would sometimes have 30+ kids including many of the top in the county showing up to run together. This gave my super-stars some kids to run with who were also low 15 instead of always running alone, and gave my 5th+ spots a group to run with instead of being strung out after the first few miles. A commitment to the 10-14mi long run definitely led to major improvements.
We went from 14th in the state two years ago to 5th this year.
Two years ago at State meet:
8th- 15:47 (So)
9th- 15:48 (So)
86th: 16:58 (Sr)
182nd: 17:50 (Jr)
214th: 18:16 (Jr)
216th: 18:23 (Sr)
243rd: 19:47 (Sr)
This year, State meet, worse conditions:
2nd- 15:18 (Sr)
3rd- 15:23 (Sr)
19th- 16:23 (Fr)
143rd- 17:38 (Jr)
165- 17:50 (Jr)
209- 18:19 (Jr)
223- 18:42 (Fr)
I've kept the workouts simple too. Building up to 3min on/90sec off fartlek reps, a "tinman tempo" plus short speed after, and the long run + taking out a workout in exchange for tempoing dual meets and often purposely sacrificing "wins" at duals to run easier and do a short fartlek plus extended cooldown after. I'm sold on it, it's just simple stuff and we have almost no injuries.