Need to dump an MPEG2 file in a loop, either to stdout or a named pipe.

This works:

$ { while : ; do cat myLoop.mpg; done; } | vlc -

This works on a text file containing "1234\n":

$ mkfifo myPipe
$ cat test.txt > myPipe & < myPipe tee -a myPipe | cat -

(it correctly loops, outputting "1234" on every line). Why does the following NOT work?

$ cat myLoop.mpg > myPipe & < myPipe tee -a myPipe | vlc myPipe

I'm primarily interested in re-writing the first statement to remove the improper "cat myLoop.mpg" statement. Will be inputting into VLC, or into FFMPEG and then piped into VLC.