Never really been much of a big fan of the wave or thumb plate deployment, as they tend to necessitate being mainly drawn from a top-vent pocket that is fairly stiff/tight. This has the potential to decrease one's versatility of carry placement options, such as in the waistband, inside a jacket pocket, belt/sheath carry, or in a billowy side-vent dress pants pocket. Although, if the blade were long and strong enough, one could use the gap as a blade trap in much the same fashion as that of a Spainsh Choil. I guess I prefer function over form.
the 1004 series was a close guess but I wouldn't pull a fast one on you guys and post a modified blade. these are all production, even if it was a limited one. As you can see the Kershaw 1004NG National Geographic Tool has a full thumbhole.
I agree with your assessment of the wave openers. I don't own one but have handled a few and they are effective if not limited to their designed purpose.
The knife in question was produced in and around 1997 before the "wave/pikal trend" (again Kershaw was ahead of the times - I think the Emerson Commander came out in 1998?) and back then it was simply called a bottle opener. As a matter of fact, with the production tip-down carry, as a bottle opener, it opens in the opposite direction to function as a wave opener. I understand other examples of this model are modified to tip-up carry to allow for wave-opening.
There were 3 production variations of this knife that I know of...a G-10 and Ti handled model with thumb-studs, a Ti handled variation with the bottle-opener cutout. There was also at least one 4th variation in G-10 with the bottle-opener.