"Like all Holmes´s reasoning, the thing seemed simplicity itself when it was once explained. He read the thought upon my features and his smile had a tinge of bitterness. "I am afraid that I rather give myself away when I explain," said he. "Results without causes are much more impressive.""
Thus said Sherlock in "The Stock-broker´s Clerk". And it is also relevant if you think about TRF. The beauty of TRF lay in the mystery of Sherlock´s appareant death and his miraculous survival and the emotions those two occurences awakened in an audience. No solution to this mystery, however brilliant, would actually satisfy the spectators, because it would rob them of this beautiful feeling of the inexplicable, woundrous thing that happened with Sherlock. The mystery explained = the mystery robbed of its charm and finally forgetable, because now it´s "simplicity itself".
I think Moftiss tried to at least partly preserve the mystery of TRF by deliberately leaving the explanation of Sherlock´s survival questionable and thus having the door for the other possible explanations still open, rather than establishing one true solution (which would always be a bit unsatisfactory). Too bad they hyped TEH with unrealistical pronouncements before they actually wrote the episode - the rift between their statements and the real episode is the main source of the fan´s disappointment, I believe. Still, I can understand why they turned their attention to personal drama of the characters rather than mysteries in S3. Sherlock´s fall in TRF created a rift between him and John that couldn´t be just waved over like in the original (it would seem very forced in this version of Sherlock). If Sherlock and John just continued like nothing had happened, we probably wouldn´t buy it either. So in TEH and TSOT they needed to resolve this tension and therefore you find more personal interactions between characters in these episodes than in those which preceded it. In HLV they then returned to classical thriller-mystery.
It was not an artistic choice to everyone´s taste, but it´s not "turning a show into romance/soap opera" either, I believe.
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I cannot live without brainwork. What else is there to live for? Stand at the window there. Was there ever such a dreary, dismal, unprofitable world? See how the yellow fog swirls down the street and drifts across the dun-coloured houses. What could be more hopelessly prosaic and material? What is the use of having powers, Doctor, when one has no field upon which to exert them?