Thanks for the post. I have one pair that I like, though I wouldn't say I like them as much as any of my AEs. The leather, while buttery soft, is also quite thin. My pair is Blake, not Blake/Rapid.
I figured the reason they were so light was a combination of thinner leather, and the thinner Blake-stitched sole vs. a thicker 360-degree Goodyear-stitched sole that also generally protrudes wider around the shoe.