Prompt from mrspencil: Holmes has to apologise to Lestrade
"Really, Watson, whatever you have lead your readers to believe, my talent for deduction does not make me omniscient. How could I have known Lestrade would go to that pub tonight, when he invariable eats at home with his wife?"
"Holmes, Mrs Lestrade left to visit her mother this morning. Lestrade said so last week, after he told you about that new case."
"The missing violets? Hardly a case, the solution was obvious after one or two inquiries. A moment's thought would have put Lestrade on the right track."
"And, perchance, did you take that moment's thought while Lestrade was still telling you about the case?"
"…perhaps, after his experiences, the inspector would appreciate a good bottle of whisky?"
"Yes, Holmes, I believe he would."