All other things being equal, a lighter shaft should produce a higher launch angle, but you're seeing the opposite result. That tells me that something about the flex point/effective loft combo of your old driver wasn't an ideal setup for you, but that doesn't say anything about the inherent superiority of the Covert driver.
Also, the numbers on that machine can't be completely accurate. Tour professionals have an average smash factor of between 1.48 and1.49.
At the end of the day, though, the precise accuracy of the numbers is irrelevant. If the numbers are "better" then it's a positive change.