The measured data is for my Bip S lite (which is a bit smaller than the Bip S). A bump of 1mm high with an area of less than 1 square centimeter is not noticable imho. My other watches also have bumps (nato strap seams, the gshock's rear plate is uneven by 1mm easy, and seiko's glass rear window...)
The spec page I linked to showing 11.4 mm is specifically for the Bip S Lite.
Maybe the lugs are included in the official specs' height/thickness. If you put it flat on the table the backside doesnt touch the surface because the lugs protrude a bit - maybe to protect the sensor from scratching. I ignored the lugs though as they're wrapping around my wrist and don't add to the thickness.
Or maybe i measure again to be sure.
We'll have to agree to disagree on that one. Bumps protruding into my skin definitely reduce my comfort wearing a watch all day. Your measurement still doesn't match the official specs and even assuming it's correct and they're all that thin it's still not close to the Pebble Time Round. 30% thicker and 60% more volume.