[whip]

"Plus, isn't the head drop just a consequence of starting the DS with a lower body/hips move, which moves the left hip nearer the target, weight more on left foot/leg, and with intention of keeping the upper body cog or head somewhat fixed, your head has to move down or spine tilt away from target, hence move your head down?"

This is a good observation. Tigers grip was strengthened, and having a strong and level left wrist is an awkward combo if you haven't tried it. Im not endorsing this theory necessarily, but there is no point of setting the radius via the level left wrist if you have no intention of maintaining that radius, or especially, if you plan to hold the face....then you need it for support. Is that the best plan? who knows, certainly not our LBG way or Homer's way, but that's the defense.
Secondly, Brian is right here....it's impossible for your head not to go down if you shift weight totally to your left leg via hip slide while maintaining a centered head. The more centered the player and less the "leaner" the less you'll see it. (Nicklaus/Gay vs. Nelson/Trevino/D.Johnson). Like it or hate it, the vertical adds snap. Consistent??? Make your own decision, but it's happening everywhere. No one told them to do it until maybe recently. We could put pictures up all day of guy's heads going down then up, down then staying there with lean, barely down and barely up. Hundreds and hundreds of victories and millions and millions of dollars also........kind of hard to call it wrong. In line with TGM, no. Ideal for consistency? you tell me.....but outright wrong?????? Would the other make them better, or would it have made them people you've never heard of? Don't know

going in order of bolded statements.....

Jtill your statement "it's impossible for your head not to go down if you shift weight totally to your left leg via hip slide while maintaining a centered head." is NOT TRUE, try it for yourself, i can do it!... it's sort of saying, 'ya homer was on the right track with the head thing but not really when it comes down to reality cuz it's impossible to really do...' reality is based on physics, geometry and the laws of the universe, a bouncing post with an object rotating around it is no good. It is most certainly possible to shift the weight via a hip slide into the left leg and tilt the axis of the shoulders with a stationary post NO BOBBING NO SWAYING its perfectly possible and to say otherwise is wrong and is calling homer wrong.

Im gonna go ahead and call the tour player head bob wrong, if its unintentional its not wrong, its a malfunction to be refined until eliminated just as with any other swing fault. If its done consciously it is WRONG and injustice to golfdom as the fate of golfdom rests partially on the shoulders of ELDRICK....which are bouncing up and down...

It would have made them better! I can guarantee it. bouncing up and down is not adding any snap or power! no matter how much it seems like it is, this is what homer calls a SEEMS-AS-IF partially the reason for the book, to eliminate the seems-as-ifs by applying law because the golf stroke is governed by only that, the laws of the universe, physics, geometry. other things they are employing to power the swing may inadvertently cause the head to drop and so it seems that the head drop is the power move, the head dropping and jumping up is not adding anything and is ALWAYS A MALFUNCTION no matter how many majors they have.