TC3 Is this even a thing that can be done on piano?
No, not in the way that it can be done on a stringed instrument or a wind instrument. Sometimes there are things notated in piano music that are strictly speaking impossible to achieve on a piano. We need to look at the context and see if we can, somehow, maybe, achieve the illusion of what is indicated. Depending on the passage in question, pedalling, rubato, control of relative note lengths and control of relative dynamics can all play a role.
One thing to try is to imagine how you think the passage should sound if it were played by a string or wind ensemble, and imagine what difference it would make if this notation wasn't there. This can help you get a feel for what the composer is trying to express with this notation, and may thus help shape the way you play it.
If you could post the passage where this notation occurs, I might have some more precise ideas.