All I'm saying is that adding recovery info to archives is probably not ideal -- we can do it in a task or media specific way that works best for whatever context the data is in.

Redundancy in .RAR made perfect sense back when you were transporting data on floppies, and if the floppy was bad, it was a huge pain. These days we transport over the network and don't need to carry any redundant data at all. All we need is a checksum and to retransmit whatever didn't arrive correctly.