How do you know that they didn't? It seems like something happened here, and if one of curbcrusher's explanations is correct - that they are finally collapsing the BS slots - it would seem that they collapsed them pretty early. And if they did, wouldn't collapsing the BS slots offer the same net outcome? (Seems worth a try on a mid-day SFO-LAX before winter's over, with "nailbiter" caveat above.)