It might indeed. Of course, Sir John's observation involved security. I was merely pointing out that there seems little at Hanbury.
Only one avenue of escape, but also only one avenue of approach by a potential threat - and the killer was armed with a knife. Escape was a near certainty to my mind; recognition would be the greater risk.
Which window would afford a view of a man crouched over a body by the steps? One the way in he could always abort the killing if seen. On the way out he would not be challenged - no-one would know a murder had taken place. Minimal risk unless he was seen and recognised IMHO.
Well, the one almost directly above the door might do. Don't forget that her head was not quite to the steps and she was about 5 feet. So the view from there should be unimpeded.
What is the likelihood of something putting their head out of the window and looking downwards in the middle of the night or very early morning?
Oh, and those next door might do nicely too.
Could you look out of that window and see a man standing in the yard of No.29? If he was a six-footer perhaps but somebody of the height of the man seen by Mrs Long? I would have thought not. Even if you saw the man, you wouldn't see the body so how much notice would you take? Cadosch seems to have been up and about, even walked through the door and down the steps - but saw nothing.
I can see that it's possible that he might be seen, but highly unlikely surely?