I’ve always liked that Pic. I believe it may be the reason Gillette chose the now famous deerstalker cap.
Anyone even slightly familiar with Holmes would guess that Dr. Watson is the alter ego of Conan Doyle.
I have a DVD about Sherlock Holmes in which there is a short film of Sir Arthur, playing with his dog then sitting on a bench and giving a brief statement about Holmes.
Conan Doyle comes across as very much the affable Dr. Watson played by Bruce.