I pulled the cable tonight. I left the outer sheath in place, and undid both ends. I forgot how bad access was behind the dash to undo the speedometer end. I didn't see any spots where it appeared to be binding, and it seemed to still have a nice coating of grease from when I did the job a few years back, but I'm going to clean it up again, and maybe squirt some lube into the angle drive, and see what happens.
If that doesn't work, I'm going to use that link on dismantling the speedometer housing, and put some lube on the spots that need it, and see if that helps.