to a certian extent. EG. if its set to 8192 bytes (8kb) then someone on 56k would have to wait 3-4 seconds longer for every one of the packets the other client didn't recieve intact but someone on ADSL would only have to wait 0.2 seconds.
If your on a fast connection STABLE connection setting it higher might squeeze a tiny bit more out of it, but overall it won't make much of a difference.
overall the standard size is perfectly fine for decent connections, and i personally AVOID pdcc aswell, cuz anythin that sends packets before an ACK can't be good.
I don't know why Khaled bothered to add pdcc to be honest, cuz something large enough to call for something to need every spare KB/s to send, is not suitable for the DCC protocol.
I have an FTPd (server) installed on mine and whenever i want to send someone a big file i just load it up and give them my address.
