Qualifies as a long read, in my book. Not sure we learn anything new but if you're a fan of Sam's you'll likely enjoy it:
To find Jamie’s mindset at any given time, Heughan takes advantage of his access to the only other person in the world who knows the character better—Gabaldon, the author who created him. “We have the same sense of who Jamie is, in terms of his essential character,” Gabaldon tells me over email. “When Sam’s prepping for a new season, he’ll ask me ‘Where is he?’ I’ll then do a brain-dump for him—just write down everything I happen to know about Jamie’s state of mind and how he feels about what’s been happening and what’s going to happen.” Heughan says looking at Jamie’s experiences collectively help him find the character, but after four years in the role, he’s almost like a muscle. “I had to go do ADR the other day, and just being back in Scotland, I noticed my accent got stronger. I feel like I can sort of turn him on and turn him off now.”