[EdZ]

Jim Furyk's swing is the living proof that you can get good impact alignments through a variety of components. It is always difficult with the whole "feel versus real" problem even for a top pro like Furyk to be sure of which component really makes him feel the clubhead. I would imagine that it is his lag sensation that is his clubhead feel ? maybe?

I am of the opinion that Jim's swing works well in the highest competition but he could swing even better with a more efficient pattern.

His natural talent makes his relatively inefficient swing work - imagine that same quantum of talent being used to power a more efficient swing!! Would I advise him to search for that swing pattern NOW ?? Only if he wants to become a global force like Woods or Els and win 4+ majors. Imagine Jim's hand eye coordination, steely grit AND a more efficient machine...

Plane is not defined by the clubshaft it is defined by the hands and the sweetspot.

The clubshaft lies on "A" plane - not "THE" plane - (unless zero #3 accumulator) it is the pressure points that should be monitored for a zero shift pattern IMO, and if you watch Furyk's hands (pressure points), you'll see that despite the odd looking motion, there is a very good reason he is as accurate as he is.... his hands stay quite close to 'on plane', on a fairly upright plane angle, for the majority of his motion.

Forget about the shaft - monitor the hands.