preparing a DV tape
 

I was reading some threads over here, and found out that most people don't recommend using a DV tape more than once.

now, I heard that most pros prepare a DV tape for shooting, by recording blank on the whole tape. When shooting on that "prepared" tape, wouldn't that be "reusing" a tape?

Yes, blacking a tape then recording over the tape (black) would result in a second pass tape. I don't black my tapes, I fast forward and rewind the tapes in the camera that is going to record on it.

what does fast forward then rewind do ?

The only prepping I do to a tape, is take the celophane off, and open the case. I also won't use a tape over, even if I felt ok with doing it only once. Save the footage, cause you just never know when it might be used.

Extended use causes the tape to stretch, and the magnetic particles to flake off.

You don't need to do anything but put it into the camera and record. Striping a tape by recording black puts excessive wear on the heads as well as the tape. A few people do that because they get continuous time code. However, all you have to do is record a few seconds of rundown at the tail of each shot, which you should do anyway, and rewind back into that area of the tape if you have removed the tape from the camera or checked a take, and your camera will pick up the time code where it left off. Professional cameras allow you to reset the time code, but consumer ones will pick up where you left off, so there's no need to stripe a tape.

In a non-non linear editing suite, you do have to stripe master tape so you can do insert editing. Also, if you want to do a digital cut (that's what Avid calls insert editing) into a new master tape at a certain point, for example, so that your program begins at exactly one hour, then you would have to stripe the tape so you can insert edit into the exact point, rather than just dubbing from your NLE to the master tape. For shooting, though, it's a waste of time and puts wear on the tape and camera.

I very rarely reuse original tapes because I file all original footage. However, I often use work tapes for copying still photos, recording sound, etc., or for personal use. Well cared-for tape is not all that delicate. Sony claims a huge number of passes for DVCAM tape, and Panasonic claims even more for DVCPRO. Often I'll make a master onto a DVCAM tape, then the client has changes, so I'll reuse the same tape, and there's never been a problem. I've seen no dropouts at all from DVCAM tapes in over 3 years.