I'm an engineering manager, so I'm all about defining a process and properly controlling it to achieve the desired output. The technical issues involving the production of a black and white print that meet the photographers pre-visualized image were defined decades ago. The steps are known. Now what to shoot is a whole other story. That's my current problem, misplaced mojo.
I can't imagine a 40x60 enlargement from a normal 35mm negative that would satisfy me technically. However, I would love to see them as they may kickstart my dormant artistic side. The Kodachrome of that green eyed Afghan girl at that enlargement would be stunning. I have projected slides (of a technical nature) where the detail was impressive at 48x72, Nikon F3 and a 55mm Micro Nikkor. I'd love to see something that size that moved me artistically.