Http pipelining is quite different. When the server takes a long time to respond to a single request, it stalls the entire pipeline. To efficiently use parallel

Http pipelining is quite different. When the server takes a long time to respond to a single request, it stalls the entire pipeline. To efficiently use parallelism you have to start multiple http tcp connections, but that is less efficient than a single connection because they all have to slow start. As for header compression, have you checked how large headers are these days? They can easily be 1.5 kb.