If I decide to bang in sick, a reserve is gonna have to get used one way or the other. The long calls are working more anyway, and there's a higher likelihood they're a commuter sitting at home. That doesn't mean it'll always be a short call sitting in a crashpad, but if I'm going be burning *someone*, I'm just playing the percentages of which dicking will likely be the least disruptive.
And I say this as guy that lives in base and bids short call if on reserve.