Understand the proposal is to show your roll and bonuses but not the target. So by infererence and being attentive you should get a good idea if the target is hittable or not, after a number of attempts.
Thus the difference isn't quite as severe as you suggest.
Personally I'm generally for giving the player either a very direct way to discover information (like putting it on the screen) or instead a fun in-game mechanic to discover and retain information. For example have your character automatically remember what values did and did not hit so as to build up game-knowledge over time. I mean, I enjoy games built around both those ideas.
As for this game, I don't imagine I'll be consulting a battle log very often (hopefully?) so when I do, I would hope it would be fully informative.