• Using perl -l gives you autochomp which Tie::File has built in. From your other nodes I see you use this frequently to add a newline when you print.
• $^W = 1; and then use Warnings; a few lines later?
• Using autodie means the script stops after the unlink line even if there is a file to delete. Why not just die if -e $file; ?
• Does $| = 1; have any effect on Tie::File? With the option memory => 0 it is already not cacheing anything.

I don't understand the point of this code. Tying to a file that doesn't exist, adding a line, then deleting the newly created file doesn't seem useful.