Watson's expression flickers with sympathy; he's never actually been particularly good at not showing his feelings on his face. He leans forward, slightly conspiratorial.

"I was in the army as well, and I know very well what you speak of, even if I did not see the same things. They are terrible phantoms to have to live with. I don't know that I can offer help as a physician, exactly... but I am able to offer help as someone else who has had his mind betray him with memories.

It's really all he can offer.