Were there any clues that the hound SH is looking for is actually H.O.U.N.D. before we see it on screen?
I ask, because I haven't found any, and would be disappointed if the writers didn't leave any clues for us to miss.
tobeornot221b made a great point in this post from another thread:
tobeornot221b wrote:
The writers take every opportunity to have Sherlock make his deductions.
I think the ketchup/nicotine stains just serve this purpose; they are the starting points for the "show off" deduction.
Sherlock could have easily identified Henry as being a smoker by smelling his clothes, but the TV audience of course isn't able to ascertain that. Visible nicotine stains enable us to reconstruct Sherlock's thoughts on this matter.
As far as I know ACD had to put up with the reproach of being unfair to his readers because they allegedly weren't able to find the solutions by themselves - until tada! Sherlock Holmes appeared with his brilliant mind. That's why ACD put all the clues and hints in the story - then it wasn't HIS fault that the readers couldn't put two and two together.
This, of course, reminds me of the Sherlock writers who claim that even someone who has watched TRF just once could tell how Sherlock faked his death - if that person would only be as clever as Sherlock...
One of the brilliant aspects of this show is the way all/most of the critical clues are hidden in plain sight. I hope I missed them, because the alternative would feel like a small cheat by the writers.