He kept the "I've changed" charade up more than most people do. But they always go back to their true selves eventually.
Yeah, unusual for him to keep that stuff up. i remember I had the "I've changed" for like...a day, then I was like "forget it, people understand I've matured, I'm older than I used to be hurr durr, moving on" but in the case of character issues, yeah JD's not going to change any time soon.