Well, my view.
Winter feeding is as an emergency and should not happen, but more and more occurs, it seems.
Spring feeding - either as winter feeding, an emergency - or, IMO, a syrup is certainly better for brood rearing.
Presumably this teacher did not feed any autumn feed, at all?
So, that is good - you have, at least, qualified your sweeping statement and it only applies to less than half the possible scenarios.
Now which spring feeding was he referring to? Emergency or brood rearing?
Regards, RAB