I don't think GSP is as much of a legacy builder for Khabib as people make it seem, especially at 155. As
@m9 mentioned, GSP would be 40 years old, basically retired for 8 years, and fighting at a weight well below his natural weight. If Khabib beat him, people would use all these excuses to discount it.
It would be a massive legacy builder for GSP if he won and he may take it for that reason. But he'd only do it if he thinks he can make the weight and beat Khabib. No offense to my man Mike Bisping, but I think going down in weight to fight Khabib is a much bigger challenge and he'd be 4 years older.
@CDJ, the inaugural 165 belt would be awesome, but Dana already said his surprise is not GSP. He has routinely shot down the 165 division, too, so I doubt that is it either. I think the surprise is going to be kind of lame. I've pretty much convinced myself that it is going to be an event in Dagestan or something like that.
....the surprise is also only going to be special if he beats Gaethje. So let's see if that happens first.