@Football Bat, there is always the question of what movements and programs might be considered to improving general physical preparedness (GPP) and what is sport-specific. As a guideline from StrongFirst, we believe that using a few, carefully chosen and even more carefully taught movements for general physical preparedness, and limiting ourselves to those few movements because they are all that's necessary for beginning and intermediate trainees in any sport. At the advanced level, coaching advice ought to come from a coach, not a book or an internet "expert."
GPP ought to be performed in such a way as to be minimally taxing to the student/athlete and therefore leaving plenty of time and energy for one's sport.
This isn't to say that the approach in the article will be wrong for all people or sports but rather that we don't support that a GPP movement, e.g., a kettlebell swing, ought to attempt to mimic the mechanics and movement patterns of any sport or class of sports. The swing is General by StrongFirst's definition, and by that definition, it will help anyone in any endeavor or walk of life who can benefit from having more General strength, and that group can even include some people who are already performing in their chosen sport at a fairly high level.
So ...
Are there any negatives to this variation of the swing?
Yes, there are positives and negatives to any exercise. This version will miss out on the concept of rooting and the vertical plank, and it will also lead to a much less stable position at the top, which in my opinion, brings with it a higher risk of injury. NB: I have no science to support the heightened injury risk but that's my gut reaction. Your mileage may vary.
And ...
Do any of you do these regularly?
No. I don't buy into the basic premise of a direct carryover from the mechanics of the swing to any sport. That doesn't mean it doesn't happen, but it's a WTH effect and not the core of our approach, which is to bulletproof you with one-arm swings and getups, and then let you do whatever sport you like. We don't swing to jump higher or run faster, we swing to be stronger and more anti-fragile, and being stronger in our chosen GPP movements helps us to be more anti-fragile and therefore more able to do just about anything else.
-S-