When transferring paper based records into Gnucash I find there it useful to have some transactions at points where I know, from a bank or other statement what the balance must really be, even if it does not match the result of the preceding gnucash transactions.
I adjust the balance by transferring to or from an equity account.
In some respects this is a generalisation of the Opening Balance when an account is created, since that must really have come from somewhere.
I record the amount these transactions should have in the transaction description, but it would be useful if this could be maintained automatically.
I can find these in my real accounts by looking in the equity account.
These anchor points prevent transactions which happened before my reconciled transactions from 'rippling through' make later balances incorrect.

It would be useful if this could be handled automatically.