Not just my part. Almost everyone else who has commented seems to make the same assumption.
argumentum ad populum

I don't think it makes the game any more enjoyable to withhold that information from the players once they have actually hit it with an attack or spell that is resisted.
Players at my table might start wondering without that information when 3 solid hits have not even bloodied a foe. Just as enjoyable, at least based on the amount of laughter at my table.
Guess we'll just have to agree to disagree.
I guess.