As another junior parent near the end of the recruiting road, I urge you some caution about getting caught up in TRN. It can be a helpful tool for understanding the historical strength of an opponent, but as with any system it has its limitations, and it can detrimentally influence your junior's mindset if you aren't careful.
In our experience, once you get outside of the top 75 players (blue chips and 5 stars), TRN's predictive accuracy is mixed and can vary by 50% or more. For example, at this last weekend's L3, just looking at players in the same grade (sr vs. sr, jr vs. jr) a player ranked 151 beat 51, 178 beat 92, 327 beat 179, and 278 beat 95, among others. That's just from one tournament site, but I'm sure there are others.
Iím not sure why the discrepancies are so big, but having watched this for a while, TRN appears to have an inherent lag with players that are improving and is slow to degrade on those that are not. Some of this may come from the question Chemist posted about "close matches" which TRN doesn't factor and some believe this can be a predictor of future movement (there are systems that factor closeness of match). I also think some of it comes from the way tournaments are aged and outlier results. A really "bad" loss will stick around for awhile, which is why some people pull their kids from backdraws.
Having talked with college coaches who recruit outside the top 75, they love the "dashboard" element of TRN and that it captures a lot of the background about a player, but they also commented that it has limitations. They referred to that 4 or 5 star recruit who was much better as a junior than in college (though it's always a guy on another team
) and they liked to talk about the 3 or 2 star diamond in the rough they found. While they use the TRN's year-on-year progression to get some sense of trajectory, a number use additional tools to give them a sense of where a junior is in their development.
Coaches seemed to understand juniors are rapidly changing physically and mentally and they want to make sure they are catching the upside of the swing, not the downside. Were all the coaches we talked with like this? No. But many of those whose program results were improving used other tools to help with recruiting. What we heard most frequently was Universal Tennis and that there is no replacement for watching a junior play.
So, if you are on the younger side of developing a junior, look at TRN as a tool, but be careful not to use it as a guidepost.