How Phil Mickelson- and YOU - can get more consistency
Recently saw a very nice interview with the fitness coach, Sean Cochran, of Phil Mickelson, The Open Championship 2013 winner. [http://www.travelgolf.com/departments/clubhouse/sean-cochran-mickelsons-trainer-qa-1302.htm] So, wondered if his swing lives up to the fitness improvements his coach has made on him. Then needed the perfect illustration to explain Phil’s swing - and found it in Phil’s (Cheetham’s, this time!) very simply explained article on the kinematic sequence (a term he has coined) which is more commonly known as the sequential summation of forces (SSF). [http://www.amm3d.com/Portals/0/ArticlesVideos/KinematicSequenceStretchingRidingFanningFinal.pdf] The world of biomechanists have probably discovered all the MAIN forces that make up a good impact (based on a study of the downswing movement patterns of the best players), but now it’s high time to move on from ‘mechanics’ to ‘bio’ - folks, there is a reason ‘bio’ precedes ‘mechanics’ in the word biomechanics. So, if you read Phil Cheetham’s article (link above) on ‘stretching’, ‘riding’ and ‘fanning’ (the latter a poor quality sequence), you know that the ‘stretching’ downswing sequence (hips starting before torso) gives the most DISTANCE (ie clubhead speed), followed by ‘riding’ (hips and torso move together at start of downswing). What he did not add is the equally important factor of DIRECTION in the swing, which can only happen with the ‘stretching’ style of downswing.
If you look at his top-of-backswing (above), think of his upper body looking like a ‘door’ facing you, the viewer. His trail (left) elbow is behind his neck, and now all the upper body can do is drop down and forward, NOT rotate, and certainly not AFTER the lower body. This is especially so as he needs to drop his trail (left) side down, because, for any left-handed golfer, with left hand lower on the grip, the left side must always be lower at impact (and at address!). See how much ‘shorter’ he is at impact (2 pics below). 
Why can the lower body not simply speed away ahead of his upper body? Especially as his coach does so much rotary fitness work with him? Because at the top of his backswing (see pic. below), his trail hip (femur/thigh) has straightened out (extended) and his lead knee had bent forward (flexed) and his lower body has to waste time straightening out these two joints from their forwards-backwards (sagittal plane) direction of bend, before they can join in the rotation that the upper body is trying desperately - as it simultaneously drops down - to make. 
So, now, despite years of practice and ‘hard-wiring’ because Phil has to make so very many independent moves at many joints, when his timing changes just the tiniest bit, his brain says ‘no time, no time, all joints aboard, the trail side is leaving, lets just GO, all together, in whichever direction we can (forwards-backwards or side-to-side or by rotating). The result - less than MAXIMAL POSSIBLE distance. MAXIMAL distance may not be that important for Phil, because his ‘riding’ style swing can produce some power (powered by muscles strengthened for him by his fitness coach!) BUT DIRECTION can never be consistent, because with such a swing the golfer must rely on last-minute hand position changes to hit the ball straight. The golfer must either ‘block’ or ‘roll-over’ with the hands at the last minute and hope it works. So, if Phil Mickelson were to wish to get MAXIMAL distance ALONG WITH great DIRECTION and TRAJECTORY, his knee, hip and trunk should be positioned so they have ONLY rotational movement (on a horizontal/transverse plane, NO forward-backward or side-to-side-rocking moves) and his trail arm should be positioned so it does not interfere with the purely ferris-wheel (frontal plane) movement of the lead arm. The only way for a golfer to get IDEAL ball-flight - maximal distance, straight (or baby-draw) direction and ideal trajectory is for the club to connect the ball on its lower inside quadrant. And that can only happen - on a consistent basis - when NO JOINT REQUIRES a CHANGE OF DIRECTION WHEN STARTING THE DOWNSWING. The same not-ideally-positioned joints which reduce ball-striking efficiency also result, eventually, in injury. The next post will be on ‘predictions for future Phil injuries’.