You are right on this. Last season was a weak year for example. Laine was not even on that competition, and Ovie won it with 101.3mph.
However, you missed the point completely. I think you suggested that that 103.something was not a reliable result as it was shot on non-NHL all star competition. I did just point out that if a 18-year-old boy can shoot 101.3mph in said official competition, it's more than likely that that same guy as an 20-year-old almost grown up man can do 103+mph.
It's not that Laine will shot 108.8 this season and it might be actually almost impossible to have that kind of slapper with a stick with only 87 flex. The point is he can (and will) shoot pretty damn hard, and in consistent manner also in next season.