For self-service style portals I highly prefer a mix of keyword based search and good overall navigation, on this class of sites I usually know what I'm looking

For self-service style portals I highly prefer a mix of keyword based search and good overall navigation, on this class of sites I usually know what I'm looking for and - at least from experience - common implementations of automatically induced semantic searches just seems to add noise without actually getting me closer to what I'm looking for. Please note that my viewpoint is largely inspired by technical queries as opposed to generalized search though. In theory I'd love a mix of both with priority on keyword results under the presumption that semantic metadata is mostly curated by humans.