Can you explain this a bit more? I dive without bailout all the time, and have done so for years. Many times I am diving vintage double hose regulators. I usually dive in a river with a current that is much greater than 2 knots (under river rapids). Having more than a single tank would be a drag issue. And I've been tangled in fishing line before; a bailout is a potential hangup on fishing line.
SeaRat
Are you talking about a rebreather?