it is not pretzel off, it is simply pretzel
and you don't need to spin onto the rail to pretzel,
you simply spin off the rail 270 degrees in the opposite motion that you got on the rail,
so, for example, if you got on a rail with your right foot forward, and spun rightside 270 off, that would be a pretzel,
or, if you got on a rail with your left foot forward, and spun leftside 270 off, that would also be a pretzel
and again you don't say pretzel off, because that is the same as saying 270 off off, it is simply pretzel,
and you don't need to spin on the rail to perform a pretzel, you can just railslide pretzel, or 270 on pretzel, etc...
get it? not many people do yet...
and a bagel is simply spinning with the motion you got on the rail,
so, if you get on the rail right foot forward, and spun leftsie 270 off, that is a railslide bagel
and, if you get on the rail left foot forward, and spin rightside 270 off, that is a railslide bagel
you can spin on to a rail and bagel aswell, say 270 on bagel. but you need to spin off the same direction you spun on... as in keep going with the motion instead of opposing it (pretzel)
the terms come from how you look when you do it. when you bagel it is a smooth buttery circular motion that is created.
when you pretzel you oppose the motion and have to turn your shoulders across your body creating a tangled look which represents an actual pretzel in real life.
there you go, no more misconceptions people can get it correct now.