Kindly disagree. I think this is a bug and this is the place for it.
Having a similar problem capturing from tape (Digi, SP and DV, all through professional Sony decks) to a 7200 rpm firewire drive using ProMAX+ Converter to Kona SD card using photo JPEG codec.
On batch capture FCP fails to recognize end of clip. Spinning color wheel; esc and force quit unavailabe; must do hard reboot. On restart, FCP has placed a series of 20 to 30 corrupt 2.99 GB files, that fill up the remaining drive space.
Have not had this problem when capturing to 10,000 rpm scsi array, though. Could be with firewire.