Ok, yeah I confirmed this was true. My laserdisc player works just fine. I think what I might try is finding a DVD recorder with SVID in and component out, use component out of the scaler to my capture device and the VGA out to use for playing on the monitor. Its a dumb amount of stuff for maybe a negligible difference to just putting the DVD recorder out to the capture card but whatever.
Oh also, my Laserdiscs have never looked better. Its just too bad 800x600 is 4:3 and most of my LDs are widescreen.
EDIT: Also, your guide to up scaling game systems is fantastic, thanks for that!