The usefulness of the B&K is that it has various signal outputs (like positive and negative video) that can be injected into a vintage TV to isolate a dead stage of circuitry.
However, as an accurate video test pattern source for setting size and linearity, it is not as good as a good test pattern DVD or an electronic cross-hatch generator. The TV Analyst is a monochrome flying spot scanner, so you can put large test pattern slides in it - but their accuracy will depend on the size and linearity settings of the B&K scanning CRT. It also contains a gated rainbow color generator, but you can get that pattern from an all-electronic generator too.
EDIT: here's a good page about it:
http://antiqueradio.org/BK1077BTelevisionAnalyst.htm