I just casually encountered a glitch where in JPIII, after the family reunion, in the hub world you have to get past a door to get to the "bird cage". As Amanda, I jumped onto the roof of the building, and swapped characters. All the characters followed Amanda and glitched through the door.
However, there is nothing to do there as I do not have the sufficient abilities, and the next level's trigger does not activate. I had to reload my save, which luckily re-positioned me outside of the building, so I could continue as normal.
This does show potential for different glitches elsewhere, although I am not sure where.
After the completing the prolouge, I found a glitch that lets Ellie Satler glitch through the gate instead of having John Hammond put in his code. I'm still working on optimizing this, but if you keep walking using ellie, all the charactors will teleport to you at the next gate, and you'll skip a 1m 20s cutscene.
Thanks Zave for letting us know, i find the prologue jump VERY useful. The fence jump needs a LOT of practicing to get it right.