Guys, the only thing I'll add is these spine thickness measurements of CKTG knives are taken right above the heel/chin, usually not far out from the handle/tang junction. On many knives that thickness tapers down (sometime quickly) as you travel down the blade towards the tip. A good example is my Ikeda AS Damascus 250: http://www.chefknivestogo.com/taik24dagy.html
. Check the video. 3.5mm thick above the chin, but tapers down into a pretty darn thin knife, especially at the tip. Overall, this is one of the three thinnest knives I own, the others being the Kono HD2 240 Funy/Gyuto, and the Takamura R-2 210 Gyuto.
Even a knife like the Sakai Takayuki Ginsan 240 Gyuto, which I liked enough to purchase, is not thin at the spine, but does include a nice distal taper in the front 1/3 of the blade. This, combined with very nice grinds down to the edge, make this knife a very good performer, despite it's heft.
IMO the overall grind of the blade and the tapering of the spine thickness throughout the blade, including any distal taper, or even just the primary bevel grind towards the tip, have more impact on performance than almost anything else.
Another case in point are the Gassan Blue #2 knives. They hold about 2mm of spine thickness almost all the way to the tip, where the grind kicks in at the end of the blade. The tips of these flow through product VERY well, despite what visually might seem to be an average or worse performer, based on looks alone. My Masakage Yuki is quite similar in this respect, yet the tip really goes well through product also. Sometimes looks can be deceiving.