I would expect Real Sense to be able to detect thin branches that are in the direction of flight. Prop guards aren't going to help much unless you fly into the trunk of a tree.
Realsense: Unfortunately technology is not able (yet) to detect thin objects like power lines, fishing line, string, tree branches smaller than your pinky finger, etc. What's worse is that sonar (which is the current OA on the Typhoon H) can not detect objects too far out or objects that are small in size. Realsense being visual is at the mercy of sight & contrast. The cameras use an advanced system of viewing what it believes to be in front of it, but it is not human and can not differentiate between what is and is not there when it comes to small objects. The sun and darkness are your enemy's in such situations. Objects in front of objects with the wrong lighting all blend together. If the object is too brightly lit, then it can't be seen. If too dark, again it can't be seen and then must rely on the existing sonar, and as we already know, the sonar is limited in range and size of object.
Propguards: Watch the many YouTube videos of Phantoms with propguards running into all types of objects (tree branches as well). Prop guards really work fantastic on a drone. The Typhoon H has six props and all it takes is one object to touch & stop one prop and that bird is coming down fast because it will throw the drone right out of alignment and into something else.
My advice to anyone who wishes to argue the above, should just wait until Realsense and the prop-guards are release and then see what the real life demos and experiences are from average users in different situations. Realsense may be the best OA on the market for hobby drones when it is released, but it will not be 100% perfect in every situation. Technology is just not yet there at this tiny price point.