>take class crucial to my major last fall (second to the introductory class)
>the professor is notorious for being super hard and failing students
>get D

>spring semester
>the professor giving the same class is super lax
>find out that half the class got As

Why the hell is this allowed to happen? Should I retake the class this spring even though an A would be simply expected for me at my level now so it wouldn't really be impressive?