It only works until the pattern of randomness consumption changes even the tiniest bit. But it's a valuable tool nonetheless, even if only for quick re-runs during a debug/fix session.

For long term regression checks you might want to make sure that your test data object graph can be round-tripped through JSON (or any similar format, but JSON tooling is ubiquitous) to get your random discoveries into a less fragile form (or: fragile in a different, more fixable way).