Renewal CHL students have to take the same test as initial students, so every instructor must cover the material in 4 hours now, and this includes range time.
Surely, you don't think students remember anything from a class five years earlier.
If five years is too long between renewal classes, how frequently should Texas require CHLs to take a class? Two years would bring it in sync with instructor renewals. That's also how often we have legislative sessions. I don't know if that's coincidence or by design.