In the block based API when we decompress simple8b blocks if we see a 0 delta value we either will append the reference object or the last value. If we see a 0 delta before seeing any delta values we know that we can append the reference object. However, as we begin and end simple8b blocks the original reference object doesn't matter anymore. We begin a new simple8b block and the first value has a 0 delta. The iterator API interprets that as appending the last value decompressed. However, the block-based API will append the reference object, which is wrong.