posted at 12/28/2013 5:44 PM EST
Kinetic energy theory (1/2 x mv^2) is based on a non-rotating object. Torque (Radius x Force) is another form of force, and must be also taken into consideration.
I've taken a few physics courses in high school and college (been 8 years since I've taken a course, so I forget all the ways to apply them), and thus I know that nothing is simple to examine when measuring energy or force. Obviously, the major force in a shot is the linear force (10 oz. puck x 100MPH shot squared). I do know also that the spin will cause the puck to be more aerodynamic, allowing the puck to sustain the same speed for a longer time. I don't think that's as relevant when it's a disc being shot from 50 feet away, as opposed to a baseball, where the spin is critical; see how long a knuckleball stays in the air at the same speed as a fastball, or how far a round rock goes as opposed to a flat rock when you throw it.
I think there may be an argument that the spin also puts a small amount of extra force into a shot, although I don't believe it makes an effect on how "heavy" it feels to a goaltender or anything like that. It may be minor in terms of how hard it hits the goalie on impact, but not a discerning difference either way. I do think that, due to the conservation of energy, that it may be harder to control for a goalie, producing more rebounds (a lesser-spinning shot off the pads will probably stop just in front of the pad, while the spin may force the puck off the pad further out).
This would be an interesting thing to do for the skills competition (although probably only eventful for hockey geeks like us) or just as a scientific experiment. Find guys with similar measured shots from the point (one who has a "heavy" shot, and one who seems to have a "lighter" shot), and make it a full length-of-the-ice shot. Measure the instantaneous velocity when it leaves the stick, and then the average velocity from when it leaves the stick until it hits the ice or the end boards to see if there's a discernable difference. Also, perhaps have a device that the puck hits, where it measures the full force felt by the puck, and compare similar speed shots from different players (heavy vs. lighter shots).
If the theory is debunked? Cool. I've always thought it was full of crap, and that the theory is pretty garbage. I think Boychuk's shot seems "heavier" than, say, Subban's shot is because Subban picks corners more often and doesn't hit goalies' chest as much, thus not leaving that lasting thought in a goalie's mind where they say "damn, that was heavy".
If it isn't? Stick companies should cash in and try to create a stick that creates more spin.