[dragonwriter]

> It works really, really well for libraries

It scales extremely poorly. It works very well for situations where there are customers/sponsors are willing to spend lots of money for quality, because then the cost scaling doesn't matter as much; research libraries, Lexis/Nexus Westlaw, etc. all do this, but it's not cheap, and the cost scaling with the size of the corpus sucks compared to algorithmic search.

It is among the approaches to internet search that lost to more purely algorithmic search, because it scales poorly in cost.