Is there any argument in defense of the TLS heartbeat extension? It seems completely inappropriate thing to stick into TLS (wrong level of abstraction), and th

Is there any argument in defense of the TLS heartbeat extension? It seems completely inappropriate thing to stick into TLS (wrong level of abstraction), and the idea of sending any kind of payload as part of heartbeat seems completely redundant (what does this achieve over just basic fields "this is heartbeen #17" -- "this is response to heartbeat #17"?