[enonevets]

"Given the current trend of MPB's with huge specs and associated huge cost, it seems foolish to me that we as developers spend that much money on what is basically a desktop machine. A machine that makes compromises due to thermals and power efficiency while actually being a desktop machine."

This only applies if you never/rarely actually use your laptop for mobile purposes. While I have a monitor and desk setup that my laptop is plugged into, I travel enough or work away from my desk enough times a year that having a laptop makes sense. I prefer having one machine over having a powerful desktop and a cheap laptop. Ultimately everyone have different preferences for how they work. You should do what works best for you.