I've been using DCC heavily for about 10 years and have had no more problems with it than any P2P apps I've used. In fact, I can't recall any major issues with it whatsoever. An occasional corrupt file, but that happens with any protocol. As I said, it may not have been designed for heavy usage and large files, and may not even be the best protocol for the job, but it works just fine.
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And I know plenty enough about the DCC protocol.
