I don't establish my bike setup from the triangle but from feel, but when I've finished it's remarkable how similar the triangles are.

Back home I have a time trial bike, an audax (now there's a British concept - most Americans wouldn't have a clue what that was), and a few mountain bikes (different ones for touring and for serious cross country, but no downhill machine). All these bikes have ended up with close to the same triangle. The harder I'll be riding a bike the more the seat is forward and high, and the handlebars far forward and low. The full suspension mountain bike I used to race on cross-countrys has the saddle about 4" higher than the bars, with a 6" stem extension. For touring I have saddle and bars at around the same height.