Special thanks to Chewing Gum, for inspiring this drabble with a review.
No matter what Watson's stories said, Lestrade was plenty intelligent enough to following Holmes's explanations and deductions. The problem was Lestrade simply couldn't pay attention to anything he said. For the sake of his sanity, Lestrade had to tune Holmes out after the first five minutes.
Dear God, that man's voice! naught but nasally screeching and growls. How the doctor put up with it Lestrade never understood. Though, perhaps, Watson employed similar methods. What could be simpler and more effective than letting one's eyes glaze over and muttering, "I can make nothing of it" and "wonderful, Holmes!" at appropriate intervals?