Erm, there's a slight difference in what those two tests are doing:
/fseek is just positioning the file pointer at the end of the file. /filter is painstakingly processing each line and sending it to the NUL device.
See the difference? And the fact that /filter is still almost as fast as /fseek alone, clearly shows that /filter is a lot faster.
If you want to test the two fairly, you have to have them do the same thing and see which one does it faster.
If you wanted to READ the data from the file, then simply /fseek'ing to the end would not be that useful, would it? Even if the bottleneck is the interpreter (which I don't think anybody ever denied?), the fact is it's quicker and easier to run through the contents of a file using /filter than it is with fopen/$fread/fclose.
