Obviously you are not impressed by Mindy's own words re hitting the ball straight. Or, perhaps you don't see his words as an explanation. In the Address section of GTTB he wrote,
"However, as the club does not roll and the clubhead is on line to the target for 18 inches or more, my swing gives a wide range and the ball can be placed as far forward as the left toe (the lowest point of the swing) or as far back as midway between the feet depending on whether a high or low shot is required."
The words "club does not roll" would seem to be a partial explanation of straightness. Richard sometimes refers to "avoiding release" but I think what he means by that is that he does want forearm-club rollover through impact. Figure 19 of GTTB clearly shows no forearm-club rollover. Release due to loss of lead arm/club shaft angle is obviously still there. Some say that no forearm rollover really means that Blake was basically hitting a controlled "push" and that he must have paid a price in reduced power.
A.J. Bonar, recently discussed at length on the SA forum, calls for aggressive forearm rollover to "hit the little homerun." Did Byron Nelson employ forearm rollover in his swing? To win 11 tournaments in a row, a pro truly must have something that none of the others had. Still, he is usually ranked behind Hogan and Nicklaus as "greatest ever." I wonder if he might have compiled the greatest record (over a long period) had he not retired so early? Perhaps the competitive drive was gone.
Lately, I have been trying to find the "ideal" Blake set up. I think my repeatability problem may be more related to set up than to movements. I am trying now to set up as closesly as possible to figures 9 and 10 of GTTB, especially figure 10. Set up that way I notice that my trail leg feels prominent, so prominent that it would be in the path of the hands if the hands were taken straight back. However, the first move (takeaway) is "out" in a line across the toes. However, the clubhead itself moves along target line (extended backwards) because the angle between lead arm and shaft is becoming acute. In what Blake calls the backswing (from end of takeaway to top of backswing) the feeling is that the clubhead is still moving along target line and clubface is staying square. At the top, lead arm has come only slightly inside. I haven't seen any other swing that has this lead arm position at the top. The overall feeling of backswing is "compactness" and "straight back-ness". The hips turn from open to square at the top. I haven't seen any other swing with this characteristic. This means the hips aren't "in the way" of the downswing, so the arms can be pulled straight down.
About the downswing Blake wrote:
"The term 'downswing' is a misnomer. It is actually a downward drag which is a combination of two movements--a horizontal rotating movement, led by the legs, which drags down the hands--and it is the backswing in reverse."
I must admit I've never been sure of what Blake meant by dowswing being "the backswing in reverse." However, one does not have to think about it. If I rely solely on the downward drag, with no apparent upper body effort, the club is pulled straight down into and through the ball. What I'm saying is that the compact, straight back, straight down swing, with clubface staying at right angles to target line throughout, makes it more likely that clubface will be square at impact. Of course, Mindy himself developed his own swing over many years, so repeatability became second nature. The simplicity of the swing (ha! you say) should make it more likely that an ordinary golfer can achieve an acceptable degree of straightness. Richard, who hits a slight fade with his driver says that he is in the fairway so often that his wife accuses him of playing "boring" golf. When I see a Phil Mickelson or a John Daly and their long, flowing driver swings, with lead arm coming way inside and club going well beyond parallel at the top, it's plain amazing that they hit the ball in the fairway as often as they do. Mindy's swing path is far less complicated, and, in my view, more likely to produce straightness. Jim