Fair enough. And it's true that LLs don't often concede that they could be more available, but through a lens where the HL is the [vociferously] demanding party, the LL is put on a defensive footing that makes them not want to concede a damn thing. And I'm not saying it's every case, but the key to successful negotiation is both sides taking emotion off the table (hard to do with sex, I know), each if them being willing to each admit there's a problem, and trusting/caring about each other enough to work through it and see it from the other side.

Every dynamic is different, and I'm not saying it's "one size fits all"; sometimes the scope one side wants is too big-- "we must agree on ALL phases of our marriage before we negotiate this one piece!"-- but there's (hopefully) a solution that both sides can live with. If they can't negotiate right, chances are they're not communicating right...which points to bigger problems than frequency, type, and duration of sex between them.