Tank Setup

[Cowfish Aesthetic]

If you plan your dive and each carry sufficient gas to get two people back to the surface safely then if you have a free flow or catastrophic gas loss or whatever you can share with your buddy.

The problem with planning on a buddy share in a free-flow situation is that you're doubling the rate of flow on your buddy's first stage in an environment that has already proven its propensity for free flow (read: cold water). And if your buddy free-flows too, better hope you're both wearing your brown pants.