yes, it does make up for it. in a vacuum, you always take a capable 2 strength player over a 1 strength player. i don't really see this one as being close, especially for the stated purpose of being a backup big. you get some pretty quality offense with that ath/lp/per/ft out of B. both are reb strengths, neither is good at defense, so thats 1 strength vs 2 for A vs B. its worth a downgrade from a non-strength to weakness to pick up a clear substantial strength in offense (or anything else, usually).
slanted players, balanced teams...