I wonder how many different interpretations have been created from these statements?
Don't we extend in every turn we make?
How could we flex if we did not first extend?
Isn't it a matter of where we extend in the turn that changes based upon the appropriate tactics for any given situation?
Isn't the trajectory of the extension what matters? It seems many associate extension movements with UP like a tree grows when in fact good extension occurs closer to perpendicular to the pitch of the slope which releases the edges to turn.
I think it is important to understand the timing of our extension movements in relationship to the timing of our edge change movements is key to understand and that owning the whole spectrum of the timing of these two movement blends is one key to a well rounded skier. To say modern skiing should only include flexing to release our edges seems short sighted.
While extending UP like a tree grows, which never permits the edges to release into the new turn, is a less efficient movement, it is one extreme end of the extension vs edge change continuum. Changing edges to engage the downhill edges before any extension movement begins, represents the other extreme of the same continuum. So to clarify, one end of the spectrum would be extending then changing edges and the opposite extreme would to change the edges then extend.
The fact is we live somewhere in the middle of this spectrum blending the timing of these two movements as the situation dictates. When skiing a slower pace we tend to begin an extension movement as we simultaneously move toward edge change. As the turning forces begin to build in excess of what is needed to turn our skis, a good skier will begin to change the movement blend to flex as the edges are released and extend during the the engagement of the new edges, which allows us to absorb some of the excess forces in the turn completion and redistribute some pressure higher in the arc of the new turn. Once we reach higher speeds and forces we move closer to the extension/retraction end of the spectrum where our flexion movements are dramatic, edge change is lightning quick and the subsequent extension movements are equally dynamic to remain in contact with the snow and redistribute pressure higher in the arc.
So we should be clear that extension movements in general are NOT bad. Extending straight against the pull of gravity (the way a tree grows) is a poor movement. Flexing to change edges all the time as a default movement seems a bit limiting as well. Every situation requires functional timing of edge change with extension and flexion to match the needs of the situation and turning forces. IMO