He didn't say he can get equivalent hardware at half price, just "equal strength", which is pretty much correct. You can get equivalent raw performance at half the price. The obvious exception is you don't can't get an equally fast SSD, but then, most people don't care enough about the extra +50% speed to pay for it. Of course there's plenty of downsides to that half-price computer vs the MBP, and the MBP provides a not insignificant amount of value for that price difference.
I personally feel the low-end 15" MBP price is overinflated. When it lost the discrete GPU and became weaker than the previous low-end 15", the price should have dropped to about $1800. That's a price where - if I needed that specific kind of configuration - I would feel it's a fair deal, whereas at $1700 it would be very good value and at $1600 a steal. Looking at the competition objectively, the $2k price is not totally out of line, though. Just stretched about as high as it can go.