The CS61 series was excessively difficult compared to the upper-level material, and it was absolutely because it was intended to weed people out of the major.
I got A's in all of my upper-level CS courses at Cal. Cryptography and compilers were a breeze compared to the CS61 courses. My average grade in the CS61 series was a B-. The semester I took CS61B (data structures), my grade on the final was 21, out of 100. The average grade was 16, and the highest score was 35. (The 35 is a VC now and is fairly active on HN.)
I got A's in all of my upper-level CS courses at Cal. Cryptography and compilers were a breeze compared to the CS61 courses. My average grade in the CS61 series was a B-. The semester I took CS61B (data structures), my grade on the final was 21, out of 100. The average grade was 16, and the highest score was 35. (The 35 is a VC now and is fairly active on HN.)