Ok, I'm going to have crack at explaining his "theory". So there are the first 3 dimensions. Horizontal, then vertical, then a cube blah blah blah, I hope you guys understand that. Once you get to the 4th, you start thinking in terms of time. To do this, let's imagine the 4th dimension is the first dimension, left to right. You travel this dimension by going Up/right the "timestream" and down/left the "timestream" Moving though these changes where you are on the time stream. Say your in timestream "A" you can travel the time stream.
Once you reach the 5th dimension, your traveling between 2/infinite time streams. This means not only are you on time stream "A" but now you can move to time stream "B" The 6th dimension would be traveling throughout EVERY possible time stream in a SINGLE universe, which is where it starts getting confusing. You're already traveling through time streams, but in the 5th I'm assuming it isn't every possible timestream, but rather, something else*. Since the Universe is physical, something we can currently actually travel in, I'm assuming each time stream is a time stream of the whole universe.
Ok, If I'm correct, say something so we can base it off of this slightly less confusing explanation, meanwhile, I would like to point some things out.
A point isn't the first dimension, its 0 dimensions, without size in ANY direction. A line is the first dimension.
Your wormhole point is good, though most of us know it already. Just to be clear, wormholes are PURELY hypothetical, at least until we know they exist for sure.
The 11 dimensions you were talking about use string theory. Now just to be clear a dimension is usually telling you where something is, not traveling, which is the misinterpreted part for most people, including me. Say the center of earth was 0,0,0,0. That's 0X 0Y 0Z 0T, where T = time. So basically I would say meet me at 45,64,6324, at 10:00 P.M. (please don't)
*Please clarify