I don't know about forever, but you can definitely shift for upwards of 50 hits, if you add a half dash every now and then. Maybe I just suck, but shifting usually puts the opponent slightly further away from me each time I do it. I need to half dash every 2-3 shifts to adjust distance.
"If someone asks you whether or not you're ticklish, it doesn't matter what you say, they're gonna touch you. If you don't wanna be touched, you gotta say something like, 'I have diarrhea. And yes, I'm very ticklish.'"