>>Maybe not if the memo is just a log - it would never have been updated, hence no unused blocks.
>
>I hear what you are saying, but I would at least try it before changing the block size. The default is 64 bytes and the smallest you can set it is 33 bytes. Unless he has over 10M records in that table, you are not going to notice a big difference. And if he changes it to 67 bytes it will get worse instead of better.

The optimal blocksize can be calculated from the lengths, that shouldn't be hard to do, but I agree the exercise may prove to be futile. There's the zero size (i.e. use actual size) option, which may be optimal for a case like this. It minimizes the unused space because it doesn't use blocks. It may have overhead somewhere else, though.