Initially, I thought lubing the inside of the handlebars was a poor idea because I needed friction (or glue) to bind them together. So I started working them together dry. After about half an hour I was halfway in and absolutely stuck. (man, this really sounds suggestive)
The problem was the incredible friction between the dry rubber and the dry plastic. For an hour I tried to get them apart by any means. Tried to use light and heavy lubes, but they could never reach the middle where the binding occurred. I just bought the NOS throttle tube, and I'm not about to break it, so I tried to slip a screwdriver in between them to release part of the binding/pour in lube.
Screwdriver ripped through the rubber side.
That's the story, and I think force might have succeeded if there was lube present. Also, being as tight as it is, there would be no problems with the grip slipping around the slide during operation.
I like the hairspray idea, but worry that it would set before I could get it in... then the same old problem would come up.
Two possible scenarios:
Manufacturer shipped two clutch-side handlebars
or
I'm an idiot.
I'm not sure which I prefer. Thanks for the advice, I was about to punch myself in the face out of frustration before posting.