John purses his lips, his expression decidedly sheepish and telegraphing his inability to remember the details he read in Sherlock's file. He was focused on the ridiculous job they wanted him to do instead and besides... this was Sherlock Holmes. He was incredible enough without added enhancements, so John didn't think about it that much. He often joked about creating and maintaining a memory bungalow to rival his palace, but that never came to fruition.

"That can't be healthy." He remarks dryly, but the offer to show John disarms him all the same. How many times was he forced to sit outside Baker Street when Sherlock wanted to go into his mind palace? More than he can care to count. He definitely isn't interested in seeing Mary shoot Sherlock and shakes his head.

"I don't want to see that. You can show me anything else you've got in there if you want, just not that. Please."