Graphite shafts in wedges. | Golf Monthly

I got a set of Mizuno irons with Aerotech Steefiber i110s graphite shafts, and then added matching Mizuno wedges with the same shaft. The shaft is a bit heavier than some graphites. I am not sure the graphite feels very different to steel, a little less jarring if you don't catch it right, like most graphites.

What was the reason the pro recommended, less weight?