I'm with the folk who weren't quite as gripped as last week - maybe just because last week there seemed to be so much riding on it all, and this week it was only really Russel Tovey's sanity and I just wasn't as bothered about him. Did love Sherlock nicking Mycroft's security pass and pretending to be him though - what Sherlock bargained so Mycroft would arrange access back into the base a second time, lord alone knows!
And when they revealed Sherlock faking the hound in the lab I thought for a moment he was doing the growls himself and almost snorted tea from my nose... 