Well Checkboard!. .On the Pegasus equipped 757's there is a feature called offpath descent. I've never used it myself, but it works by one enters a point or a fix on the page, and the altitude one whises to be over that point/fix. Then the FMC shows two circles around that point, one circle where one must start the descent in clean configuration to reach that point at that predeterment altitude, and the other circle (in different color, don't remember what) inside the other one, where one must start the descent with the speedbrakes fully extended.. .Hope it helps.. .Fresca