So, yah- it's completely possible to execute fidsift.sh via tanstaafl's batch file (ethernet) while viewing a Hyperterminal session (COM1).

The batch file is working well now. I suppose there must have been something about ftp connection time-outs during the time that fidsift.sh was trying to do its job. Running the file directly via Hyperterminal the first time seems to have sorted everything out. The batch file can easily take care of shorter sortings.

I was getting 'nomem' errors regularly after running the batch file sifts, so I added one more line to fidsift.txt file:
literal site reboot
No more worries after a reboot!