I haven't looked at LOT in detail, but I suspect they're complementary approaches, and compatible in the sense that an organization could make both commitments.
Several months ago EFF published a guide to alternative patent license arrangements that mentions both, see https://www.eff.org/deeplinks/2014/05/hacking-patent-system-...
Google has a comparison table at http://www.google.com/patents/licensing/comparison/ that ought be updated to reflect DPL as actually used now.