I've been becoming familiar with a lot of streaming protocols in the past few years, but now that I ask myself, I don't know what are the advantages of protocols such as HLS or HDS which chunk the stream compared to a direct-from-memory bytestream like HTTP octet-stream, RTMP or RTSP can do for example.
I would think that the I/O necessary to produce the fragments makes it less efficient and, for HLS, TCP already insures data reliability, so is it not redundant to use an MPEG Transport-Stream over TCP?