with live stuff, the level should already be sorted before it hits the encoder
so i can't see it hurting to just enter a number in the CLI, then let the DRC handle the rest. if it's a little off it shouldn't hurt too bad. considering other encoders rely on user input, there's no reason aften can't too
perhaps a "-live" switch or similar could be added so aften knows how many passes to do? or perhaps 2-pass should be specified explicitly (that's probablythe way to do it).