[EricH]

I would say that the vast majority of teams do it something like this:

The "training team" is better known as the "FTC team" or the "VEX team" or maybe the "FLL team". They still compete, just as a different team, or set of teams, at a different level. It's actually not uncommon for an FTC team to "come up" to FRC and do fairly well; going the other way for a season or five is also common.

Or maybe the team operates an offseason training course, often with a competition element (either FRC offseasons, or OCCRA or some other robotics competition).

Or, what a few teams do, is have two competition teams, one being primarily underclassmen and the other being primarily seniors. (11 and 193 use this approach; I believe a few other teams have done this in the past.)

Of course, being a little farther from most other active FRC teams than usual makes some aspects of each of those rather difficult.