“Cliffhanger” is perhaps not the right word for it since we knew Sherlock was alive anyway.
The more I think of it, the more the problem lies with the original Sherlock Holmes and the whole tendency he spawned of making sure your detective had an eccentric personality or something remarkable about it. The point of comparison is probably a dull police functionary like Simenon’s Jules Maigret. He smokes the pipe, he’s got a wife, but everything else you know about it is business-related.
Everything you need to know about the detective should be related to his job. None of that garbage about growing orchids or waxing your moustache or being a gourmet (for some reason, they all are), unless you’re investigating Murder at Maxim’s, or giving him some other peculiar trait like OCD or Tourette’s or whatever (see how the whole Adrian Monk show went). Everything you’re taught about him should have been told you in relation to the investigation. Apply that to Sherlock Holmes and he comes across like a Mary Sue. “Tobacco ashes! Did you know, Watson, that I wrote a monograph on tobacco ashes?” Even the more restrained characters seem to suffer from this - when they’ve adapted Leroux’s The Mystery of the Yellow Room a few years ago, they figured out that “precocious enterprising reporter” was not particularly credible nowadays, so they multiplied open allusions to Tintin, whom he preceded by a quarter of a century.
Miss Marple is better, in that at least her deductions involve drawing on village life (“like that time Mrs. Smith bought too much canned meat”, etc.). And I’d put Columbo as part of the Marple tradition (even though the whole cigar, trench-coat, old-foreign-car and dachshund portrait is too much to bear) if only because he’s occasionally referring to stuff that his wife does that bears some relation on what is being investigated.
In other words, dammit, I want a dull detective. Someone whom you only encounter through his job. But please please please no more CSI “tadaa, science!” bullshit. I find myself increasingly attracted to true crime stuff, and I don’t think anyone does it better than the French. The Americans tend to worship cops too much to really get introspective about cases, and the British are too reserved.