I'll share another that I find strange. Maybe someone else has had the same experience.
I've converted some HZ Super Cubs to 72mhz radios so I can use trainer boxes with them. This is the primary plane that I use to teach a newbie. The next plane that I let them fly is either the T-28 or the Hobbico Avistar.(unless they have their own trainer plane).
By accident, I've discovered that if I let them fly the Avistar on their second or third buddy box flight, they seem to do much better with their next flight on the Super Cub. I'm not sure why, I just know it works.