I think you're thinking of cases where there is a search warrant and the potential harm to third parties has been weighed against the needs of the investigation

I think you're thinking of cases where there is a search warrant and the potential harm to third parties has been weighed against the needs of the investigation, which should be predicated on a robust assessment that determines that this particular case justifies the harm. I don't think leaving the decision up to the agent at the point of entry, or basing it on some kind of random selection, is as robust as a good quality court issuing warrants. Though I'm contradicting my point elsewhere in this discussion about being generally skeptical of such courts.