Direct threading and indirect threading both rely heavily on the indirect predictor. You might even say that direct threading relies more heavily on indirect predictor state and in particular the contents of the IBTB because it has so many more branches and so more opportunity to store per-location history for particular instructions and hence more to lose if the IBTB is flushed.

Indirect threading relies more on strong and deep history pattern matching at a single location, and probably uses less state overall.