The Validity of a Heuristic Explanation of Black Hole Complementarity? In one of the messenger lectures at Cornell in 2013, Leonard Susskind gave a heuristic argument for black hole complementarity. Suppose Alice is stationed far away from a Schwarzschild black hole and a particle Bob falls freely through the event horizon. There is a conflict of principles in the sense that Alice would believe that the event horizon is very hot for Bob, and think that Bob will be burnt, while Bob will theoretically experience nothing special, given the equivalence principle. 
Here is Susskind's argument to resolve the apparent conflict: When Bob is a distance $\lambda$ away from the event horizon, Alice wants to tell if Bob has been burnt by doing an experiment(i.e. by shining photons at Bob and measuring its position). However, in order to resolve Bob (to reduce the measurement uncertainty to below $\lambda$), Alice has to shine photons of short enough wavelength and thus high enough energy (due to the diffraction limit of optics, used in Heisenberg's heuristic demonstration of measurement uncertainty principle). It turns out that by trying to measure the position of Bob and detecting whether or not it has been burnt, the photons sent by Alice would have burnt Bob anyways. So there is some kind of complementarity in place.
However, the argument seems to break down given that the diffraction limit has been broken in recent years by quantum measurement techniques (for example, see this paper by Mankei Tsang). So is it possible to modify Susskind's argument to make it still work? Or is there a more technical and fundamental argument that will circumvent this problem? 
Any suggestions for readings related to this topic would also be nice!
 A: Susskind's original argument doesn't work. Alice just needs Bob to send a message to her saying "I'm still alive!" She doesn't have to illuminate Bob.
Of course, it's hard to get a message out from the near-horizon region of a black hole because of the redshift, but there's no theoretical reason that this shouldn't work. Suppose you don't have a illumination source that's bright enough to make it out from the black hole near-horizon. Just send a sequence of Bobs in, one following another. The $k$th Bob picks up the signal from the $(k-1)$st Bob and relays it to the $(k+1)$st Bob. This system will get the signal to Alice no matter how much it is redshifted1. 
One could even replace all the Bobs by automated probes if one has moral objections to suicide missions.
1This is the way that optical fiber works; there are repeaters stationed every 100 km or so to keep the signal from fading too much to be detectable. A signal could never make it 5000 km over an optical fiber without repeaters, but people regularly call California from New York with very little noise. 
