Why doesn't the tape trick work with scotch tape?

[Twigg]

Mods, I know "General Engineering" hardly describes this question, but it doesn't seem to fit anywhere. Move it where you wish.

There's a trick that works with most tape (especially packing tape), where you fold the tape on itself, make a crease, then pull the creased tape apart quickly. The tape will tear neatly apart, and it spares you the effort of finding a pair of scissors. For a video demo, check out "method 3" of this video.

Today, I tried to show off to a coworker using this trick to tear scotch tape, and I made a big ol' fool out of myself. I know I can do it with most kinds of tape. What gives? Is scotch tape more elastic? Thinner? What parameters do you all think are critical? My dignity is at stake here

 

[Rive]

scotch tape

Could you please give more details? I could not find anything conclusive about the material or function of this particular tape type.

 

[Vanadium 50]

Also, 3M makes a zillion kinds of tape, all branded "Scotch".

 

[Twigg]

Sorry about that. Should've known better than to post right before bed.

3/4 inch "Magic^TM Office Tape" under the Scotch brand.

What I observed was that the tape wouldn't tear, it wouldn't even plasticly stretch, it would just elastically snap back to its original shape and resist the pull.