Today, I deviated from my FMC programmed course of flight by kicking into HDG SEL mode a few mins after takeoff. After flying in this mode for a couple of minutes, when I hit LNAV, the FMC said I was not on an intercept heading which I had expected. Usually, I rectify this by steering a course back toward the magenta line using the HDG window and HDG SEL mode until LNAV re-arms and I rejoin the magenta line. Today, however, I decided to delete the waypoint I'd been heading to before kicking into HDG SEL mode and bring the next waypoint up in its place. This gave me an INTC CRS option on the FMC which I just accepted ("EXEcuted") and to my surprise, when I clicked the LNAV button on the MCP panel after that, the 744 started a beautiful turn directly toward the magenta course line despite the fact that it was about 160 degrees behind and miles away from me.Is the Queen supposed to do this? Did the FMC basically tell the FD/AP that I had entered an intercept course and even though it was behind me and miles away, to turn the bird around using LNAV because I had satisfied the key criterion for FMC course re-engagement?Jonathan

Moving a waypoint to the top of the legs page, then executing it, tells the FMC you want to go directly to that waypoint from your present position. Therefore no intercept required.