There's a likelihood of things being done incorrectly by a trainee, which is why I don't think the best course of action in learning to correct errors in the ledger + historical ledger is to create a test patient in live mode. When this isn't done correctly, it has a direct effect on the accounts receivable figures in the office. Training something as important as GAAP and line item accounting in the ledger should really have it's own demo/training program within the sample database.