I think your speculation about Sherlock S3 being the last might be entirely accurate. By then, most of the biggest stories will have served as material, with the Fall being almost nicely in the middle of things, so we’ll have both before and after. Plus I think nobody would ever want to risk Sherlock becoming boring in any way. After all, writing three small movies every season is hard to keep up. The producers and writers have however often stated that they’d like to do an old-age-season later.

All true!  But of course it’s just us guessing for now.

Ugh.  I can live with waiting for S3, but I really would like to know early whether it’ll be the last season or not, so I know whether to brace for it.

You know what I worry about, though?  If the cast or crew members start taking hate for the schedule getting pushed back due to their success.  I like to think people aren’t that narrow-minded and entitled, but if it happens then I’ll freaking CHEER if the show ends.  That sort of asininity does not deserve to be rewarded or encouraged.

Oh my GOD, though, an old-age season would MURDER ME.  Cold blood.  Premeditated.  Somebody get Sherlock on that case and avenge me!