'I really don't quite understand yet how this is going to work, exactly' is kind of hard to square with 'The solution to Scalability'. If one does not understand all the considerations, how is one able to meaningfully advocate it as any kind of solution?
Like anything else in life, if it's difficult to figure out at first, then continuous exposure to the logic of the inner workings will eventually bridge the gap. That's how I learned about Bitcoin; not over 2 days worth of reading/thinking, but over 4 years. I'm still going.
I have been here for a while and as a non coder and pretty average IQ person I have done a good job in understanding the various BIP's in a logical and understandable way but this segregated witness one is probably too abstract for me to understand. It sorts like a way to efficiently compress the weight of blocks by removing something that's not needed when possible.