Is this the extra, null byte so that comparisons work out? Thinking about this more, this isn't going to guarantee our sort order works out, because the other array may have null bytes itself to represent null array elements. We'd need to only compare the data that represent the actual array data and not the header data.

So let's not write this byte. I've already disallowed comparison of arrays with the <, <=, >, >= so we're fine for now. We'd need to special case our comparator to get this right. We can do this later - it's not a 3.0 requirement.