I took my Trek to my (new) LBS and discussed assorted options to get more water on that bike as it only has a place for one water cage. We determined that there is no way that I can get both a seat-post mounted water bottle holder and a seat-bag on it - and the bars are too thick to mount a handlebar holder either. He suggested that when it comes to the Trek that if I need more than the one water bottle to just break out my Camelbak. He made the point that filling it with ice will help cool my back

The LHT gives far more water options, which is good - we just need to fit it to me so I can ride it long enough to need water