Trainer Kits would serve a purpose if they actually resembled proper decks. Not having enough trainers makes them HORRIBLE teaching tools. (Even Theme Decks are a LOT better in this regard...) Only the HGSS and BW ones had a decent array of Trainers. (Though the BW Trainer Kit suffered from unbalanced Pokemon. Excadrill is by far the best card in either deck, and hits the other deck for weakness as well, though I guess this doesn't matter much for the guided-duels that Trainer Kits are kinda intended for, not that I think many people go through them.) The last couple in particular (the Latias/Latios one and the Pikachu Libre/Suicune one) were terrible.
If you're going to teach people how to play the game, you need to include more trainers and less Pokemon. "Run every Pokemon you can and don't worry about Trainers" is not a good precedent to set for new players. They should be encouraged to look at their options. Considering the only options for most of the Pokemon typical of Trainer Kits is attach energy to your active Pokemon and use its highest-damaging attack, it's not a very good way to learn the game. (They're too linear. There's never a point where you have an option of what to do. I know they're guided duels, but they could at least have multiple things you could've done even if you're forced into a specific choice, to get players to think about potential plays in the future.)
I wonder if the "great game tips" are any use to new players. I'm guessing it's just the simple "don't run too many types" type stuff. Either way, it's obviously a throw-away line that doesn't really mean anything.