Research on Maigret often focuses on Simenon’s "Realistic Twist" and how the character redefined the detective genre by moving away from logic-based problem solving toward psychological empathy.
But the pipe is also a metaphor for the reading experience. The pipe is slow. It requires patience. You cannot smoke a pipe while running a marathon. Similarly, you cannot read a Maigret novel for the plot twist. You read it for the texture. Maigret