Video resolution specs

[DVtyro]

The other day I was reading Umatic SP specs in a late 1980s magazine, and it said: 330 lines in monochrome mode, 240 lines in color mode. Well, I know that Umatic only has about 30-40 lines of chroma resolution, it is as pitiful as any other color-under format. So, what did they mean?

Did they mean that without chroma, the signal is cleaner, there is no interference, so it actually does provide higher resolution ON TAPE?

Or did they mean that colorful picture LOOKS less sharp to a human eye?

Or something else?