It seems each of the two sets should increase a certain (and different) pair of stats and this is true for the Warlock. However, for the Titan, the Monitor Type 2 leg piece increases Disciple and Strength when it seems like it should increase Intellect and Strength. The situation is even more messed up for the Hunter, with the chest pieces and leg pieces (IIRC) seeming to have the wrong stats on them. If someone at Bungie tells me the current stat allocation is by design, so be it, but it looks like a bug to me.