I think he was trying to recite prepared/memorized responses last night and his responses in 2012 seem more off the cuff/improvised. I think he had a lot more issues with his stutter last night because they went with a strategy of having him memorize a bunch of prepared responses to Trump’s lies. If I’m doing trying to recite memorized lines, I have to have to practice those lines a ton and I have to have them down perfectly to not stutter. I typically don’t have as much of an issue with stuttering if I can improvise my lines a bit. I used to write down key subjects/points I needed to hit on note cards and I’d just talk to those points instead of memorizing lines and that worked pretty well.