I enjoyed this episode more than I was expecting to, based on some of the other reviews here. The reviews are incorrect however - this story is from EARLY in The Canon (1891), not late - so it came as no surprise that the conclusion of the reviews was well, a matter of opinion. The fact that Granada chose to mix and match stories from 'The Adventures..' into 'The case-book..' was odd, but does not change the order in which the author wrote the originals!
The episode featured the usual remarkable performance from Jeremy Brett and an excellent supporting cast. Peter Vaughan was wonderful as Turner. The silent exchange of glances between him and Holmes was glorious, moving and superbly executed by both actors, even if not quite true to the original (where Holmes 'reads' Turners weary look, rather than having an 'eyes only' conversation with him!).
Odd that a screenplay so faithful to the original should omit both the coooeee and the 'grey cloth' clues. Why? It made no sense! I'm sure Holmes himself would struggle to explain THAT decision....especially as it robbed him of the 2 of the strongest links in his chain of events.
Still, the wonderful acting, superb sets and still generally excellent production values (notwithstanding the above) were enough to make this episode worth watching and nearly as good as the earlier ones, despite dear Jeremy's failing health.