It's kind of apples and oranges, but lcd's do scan similar to crt's. Hence the refresh rate which presumably is as critical or more so with lcd's.
This KDS isn't particularly hot. This asus 21.5" lcd has some use on it, but has that same "splendid" sticker I still see at Best Buy. Overall the kds looks noticeably dim by comparison. But it's blues and magentas are richer. Put a trinitron up against a more or less revent lcd and you have a basis for comparison. The kds is kind of drab. But at least it has "depth"
All I know is lcd's are rated for their response time, in the milisseconds.
Modern lcd's must hav different levels of persistence, and perhaps call for a higher refresh rate. These high end monitors which have response times in the single digits, and are much sought after by gamers, can't possibly have the same persistence you're talking about. If the image persists for too long, refresh to a large degree and response times, or whatever the exact terminology is, are of no consequence. Some professional gamers make millions of dollars, and you can be pretty sure they're no gaming on run of the mill lcd's.
But as to the visible absence of scan lines on lcd's, it's something I haven't noticed or paid much attention to.