I have two senarios where this will work well for external devices. First, USB flash drives and hard drives may have broken connectors and this results in the device possibly needing to be held in place for recovery/transfer purposes, and the device can frequently disconnect from the system. The second is that a device may simply malfunction and disconnect a USB device, resulting in the path no longer being valid. It would be very helpful is teracopy presented the option to wait for the path to reappear when a network or local path disconnects, as long as it's not from a cause like deletion or something that can't be remedied.

This problem can be mitigated in version 2.12 by setting an extremely large RetriesMax  value e.g. 90000 then as long as the outage isn't too long it will recover. However a better solution would be to add a retry delay along with the maxReties so that it could be set to check every n seconds or milliseconds (ranging from current default to about 1 hour) that way if there is a short outage then you could set it to retry a total of 10 times with a 3 minute delay for example to allow it co complete if the network is down for less than 30 minutes.
I have experienced the problem above with a VPN connection which dropped for a few seconds and solved the problem by picking a huge number of retries.